GAGELER J.
Introduction
This special case, in a proceeding in the original jurisdiction of the High Court, raises questions about the constitutional validity of Div 4AA of Pt VII of the Police Administration Act (NT), enacted by the Northern Territory Legislative Assembly in 2014. The Division was explained in the course of its enactment as implementing the "concept of paperless arrests", the underlying policy being "to permit police officers to detain individuals for up to four hours in relation to public order-type offences".
Division 4AA authorises a member of the Police Force of the Northern Territory to detain a person whom the member has arrested without warrant on the basis that the member believed that the person had committed, was committing or was about to commit a prescribed offence for which the person might be issued with an infringement notice requiring payment of a specified amount in order to expiate the offence. The authority given to the member is to detain the person, for up to four hours, or for longer if the person is intoxicated.
The first plaintiff, North Australian Aboriginal Justice Agency Ltd, provides legal services to Aboriginal and Torres Strait Islander people in the Northern Territory. The special case contains agreed facts which demonstrate that the vast majority of those detained under Div 4AA in the first quarter of 2015 were Aboriginal or Torres Strait Islander people.
The second plaintiff, Ms Bowden, is an Aboriginal person who is resident in the Northern Territory. She was arrested without warrant by a member or members of the Police Force at Katherine, following which she was detained under Div 4AA at the Katherine Police Station from approximately 5.40pm on 19 March 2015 until she was released at 5.20am on 20 March 2015. On release, she was issued with an infringement notice requiring her to pay a total amount of $274.00 in order to expiate offences specified in the notice as using obscene language and indecent behaviour and bringing liquor into a restricted area.
Both plaintiffs seek against the Northern Territory of Australia, as defendant, a declaration to the effect that Div 4AA is invalid. The second plaintiff also claims damages for wrongful imprisonment. The defendant takes no issue as to the standing of either plaintiff. The pleadings have closed, but the facts relevant to the wrongful imprisonment claim have not been found and are not fully agreed.
The special case raises questions which are agreed by the parties to arise from the relief sought by the plaintiffs. The two substantive questions ask whether Div 4AA is invalid either because it infringes the doctrine of separation of powers enshrined in Ch III of the Constitution or because it impairs the institutional integrity of courts capable of being invested with the judicial power of the Commonwealth.
Underlying both questions is an anterior question as to whether the detention authorised by Div 4AA is penal or punitive in character. Informing the answer to that question of characterisation is a threshold question of construction to which it will be necessary immediately to turn after setting out the critical provisions of Div 4AA and locating Div 4AA within its broader legislative context.
Legislation
Within Div 4AA of Pt VII of the Police Administration Act, the critical operative provision is s 133AB, the first sub-section of which provides:
"(1) This section applies if:
(a) a member of the Police Force has arrested a person without a warrant under section 123; and
(b) the person was arrested because the member believed on reasonable grounds that the person had committed, was committing or was about to commit, an offence that is an infringement notice offence."
There are thus two conditions for the application of the section.
The first condition is that a member of the Police Force has arrested a person without a warrant under s 123. Section 123 provides:
"A member of the Police Force may, without warrant, arrest and take into custody any person where he believes on reasonable grounds that the person has committed, is committing or is about to commit an offence."
The second condition is that the person was arrested because the member believed on reasonable grounds that the person had committed, was committing or was about to commit an offence that is an "infringement notice offence". That expression is defined for the purpose of Div 4AA to mean an offence under another Northern Territory Act "for which an infringement notice may be served and which is prescribed for [Div 4AA] by regulation".
The definition is framed to pick up provisions of other Northern Territory legislation allowing for the service of infringement notices. An infringement notice is a notice to the effect that the person to whom the notice is directed has committed a specified offence and that the person may expiate the offence by paying the penalty specified in the notice. The person served with the notice can elect to pay the penalty within a specified time, in which case the offence is automatically expiated by the payment. Alternatively, the person can elect to have the matter dealt with by a court, in which case proceedings may be taken against the person in respect of the alleged offence as if the infringement notice had not been issued.
Offences for which infringement notices may be served and which have been prescribed for Div 4AA by regulation, so as to fall within the definition of an "infringement notice offence", comprise specified offences for which a member of the Police Force is able to serve an infringement notice under the Summary Offences Act, the Liquor Act and the Misuse of Drugs Act (NT). The total number of prescribed offences is 35. They range in seriousness from playing a musical instrument so as to annoy or failing to keep a clean yard, to cultivating a prohibited plant or possessing a dangerous drug.
The penalties for many of those infringement notice offences, if dealt with by a court, are limited to fines. The penalties for others, including the two offences specified in the notice issued to the second plaintiff, extend to imprisonment for a maximum of six months. For the two most serious infringement notice offences, both under the Misuse of Drugs Act, the penalty extends to imprisonment for a maximum of two years.
Each infringement notice offence is within the jurisdiction of the Court of Summary Jurisdiction constituted, for the purpose of hearing and adjudication, by a magistrate or by two justices of the peace. A proceeding for such an offence is commenced in the Court of Summary Jurisdiction by the making of a complaint to a justice of the peace or to a magistrate, and a party to such a proceeding has a right to appeal from an adjudication of that Court to the Supreme Court of the Northern Territory.
The two conditions for the application of the section being satisfied whenever a member of the Police Force has arrested a person without a warrant under s 123 for an infringement notice offence, s 133AB goes on to provide:
"(2) The member may take the person into custody and:
(a) hold the person for a period up to 4 hours; or
(b) if the person is intoxicated - hold the person for a period longer than 4 hours until the member believes on reasonable grounds that the person is no longer intoxicated.
(3) The member, or any other member, on the expiry of the period mentioned in subsection (2), may:
(a) release the person unconditionally; or
(b) release the person and issue the person with an infringement notice in relation to the infringement notice offence; or
(c) release the person on bail; or
(d) under section 137, bring the person before a justice or court for the infringement notice offence or another offence allegedly committed by the person.
(4) For deciding how to deal with the person under subsection (3), the member, or another member, may question the person about the infringement notice offence, or any other offence in relation to which the person is of interest to police."
The structure is plain enough. Section 133AB(2) authorises the member of the Police Force to detain the person arrested for an infringement notice offence for a period of up to four hours, or longer if the person is intoxicated. Section 133AB(3) gives that member, or another member, four options as to how to deal with that person at the end of the period of detention. Section 133AB(4) authorises that member or another member to question the person for the purpose of determining how to so deal with the person.
The four options given to a member of the Police Force under s 133AB(3) need to be examined in turn. The first three involve releasing the person at the end of the period of detention.
The first option - releasing the person unconditionally - requires no comment, other than to note that it is the only option which would result in the arrest that has occurred being "paperless".
The second option - releasing the person and issuing the person with an infringement notice in relation to the infringement notice offence for which the person has been arrested - involves an exercise of a power conferred on a member of the Police Force by the other Northern Territory legislation which provides for the issuing of an infringement notice for the offence. The issuing of the notice permits the person to elect to pay the specified amount and expiate the offence, or to have the matter dealt with by a court.
The third option - releasing the person on bail - involves an exercise of a power conferred on a member of the Police Force by the Bail Act (NT). Under the Bail Act, release of a person on bail by a member of the Police Force can occur as an alternative to bringing a person before a justice or a court of competent jurisdiction under s 137 of the Police Administration Act. It can occur only after the person has been charged, and is ordinarily to occur within four hours of the person being charged. Charging a person with an offence requires particulars of the charge to be entered in a Police Station charge book unless it is not practicable for that to occur. Whatever the precise significance of charging a person, it must be taken in this context to be a precursor to prosecution for the offence charged in a court.
The final option available to a member of the Police Force under s 133AB(3) is described in s 133AB(3)(d) in terms of the member acting under s 137 to bring the person before a justice or court for the infringement notice offence or another offence allegedly committed by the person. Section 137(1) provides:
"Without limiting the operation of section 123, but subject to subsections (2) and (3) of this section, a person taken into lawful custody under this or any other Act shall … be brought before a justice or a court of competent jurisdiction as soon as is practicable after being taken into custody, unless he or she is sooner granted bail under the Bail Act or is released from custody."
Sub-sections (2) and (3) allow for a person taken into lawful custody in some circumstances to continue to be held in custody for such period as is reasonable to enable the person to be questioned, or investigations to be carried out to obtain evidence of, or in relation to, an offence which involves the person.
For a member of the Police Force to bring a person before a justice or court for an infringement notice offence, or for another offence allegedly committed by the person, is for the member to bring the person before the Court of Summary Jurisdiction and to make a complaint that the person has committed the offence in question. The making of that complaint constitutes the commencement of a proceeding by which the guilt of the person and any punishment for the offence will then be determined by the Court of Summary Jurisdiction, subject to an appeal to the Supreme Court.
The evident law enforcement function served by Div 4AA is to be contrasted with the evident protective function served by Div 4. Division 4, which predated Div 4AA, authorises a member of the Police Force to apprehend without warrant a person who the member has reasonable grounds for believing is intoxicated and is either in a public place or trespassing on private land. The member must have reasonable grounds for believing that, because of his or her intoxication, the person: is unable adequately to care for himself or herself and cannot practicably at that time be cared for by someone else; may cause harm to himself or herself or someone else; may intimidate, alarm or cause substantial annoyance to people; or is likely to commit an offence. The person so apprehended can be held in custody for no longer than it reasonably appears that the person remains intoxicated, and is then to be released. The person is to be neither charged with an offence nor questioned in relation to an offence.
Construction
The constitutional validity of Div 4AA turns on the character and consequences of the detention authorised by s 133AB(2)(a). The character and consequences of the detention authorised by s 133AB(2)(b) need not be separately considered. That is because no party or intervener argues that s 133AB(2)(b) has a severable operation.
The threshold question of construction informing the answer to the question of characterisation concerns the measurement of the period of "up to 4 hours" for which s 133AB(2)(a) authorises the member of the Police Force who has arrested a person for an infringement notice offence to hold that person in custody.
The plaintiffs argue that s 133AB(2)(a) authorises the member of the Police Force to hold the person in custody for any period up to a maximum of four hours. Just how long the person is held up to that four hour maximum is for the member to determine.
The defendant argues that s 133AB(2)(a) authorises the member of the Police Force to hold the person in custody only for so long as is reasonable for that member or another member to make and to implement a decision to deal with a non-intoxicated person under s 133AB(3). Holding under s 133AB(2) is for the purpose only of dealing with under s 133AB(3). The four hour maximum is a legislative cap on the time that can be regarded as reasonable.
The defendant also has an overlapping argument. It is that s 137(1) operates concurrently with s 133AB(2) so as to require that a person who has been arrested and taken into custody for an infringement notice offence be brought before a justice or a court of competent jurisdiction "as soon as is practicable" after having been taken into custody. Section 133AB(2)(a) sets four hours as the upper limit of what can be regarded to be "as soon as is practicable" for the purpose of bringing the person before a justice or a court in compliance with s 137(1). To exercise the last of the options given to a member of the Police Force by s 133AB(3) is to do nothing more than comply with the concurrent requirement of s 137(1). If one of the other options given to a member of the Police Force by s 133AB(3) is to be exercised, that option must likewise be exercised within the same time frame: as soon as practicable, but always within the four hour period.
The arguments divide along battlelines not unfamiliar where questions about the constitutional validity of a law are abstracted from questions about the concrete application of that law to determine the rights and liabilities of the parties. The party seeking to challenge validity advances a literal and draconian construction, even though the construction would be detrimental to that party were the law to be held valid. The party seeking to support validity advances a strained but benign construction, even though the construction is less efficacious from the perspective of that party than the literal construction embraced by the challenger. The constructions advanced reflect forensic choices: one designed to maximise the prospect of constitutional invalidity; the other to sidestep, or at least minimise, the prospect of constitutional invalidity. A court should be wary.
"If the choice is between reading a statutory provision in a way that will invalidate it and reading it in a way that will not, a court must always choose the latter course when it is reasonably open." The nature of that mandated choice must not be misunderstood. The choice, where binary, is between two constructions: both of which are reasonably open in the application of ordinary principles of statutory construction; one of which is in opposition to the Constitution, the other of which is in conformity with the Constitution. Questions as to the severance or reading down of otherwise invalid provisions aside, a court has no warrant for departing from ordinary principles of statutory construction in pursuit of constitutional validity. And a court has no warrant for preferring one construction of a statutory provision over another merely to avoid constitutional doubt.
The approach which a court should adopt was identified and explained in the following statement by French CJ in International Finance Trust Co Ltd v New South Wales Crime Commission:
"The court should not strain to give a meaning to statutes which is artificial or departs markedly from their ordinary meaning simply in order to preserve their constitutional validity. There are two reasons for this. The first is that if Parliament has used clear words to encroach upon the liberty or rights of the subject or to impose procedural or other constraints upon the courts its choice should be respected even if the consequence is constitutional invalidity. The second reason is that those who are required to apply or administer the law, those who are to be bound by it and those who advise upon it are generally entitled to rely upon the ordinary sense of the words that Parliament has chosen. To the extent that a statutory provision has to be read subject to a counterintuitive judicial gloss, the accessibility of the law to the public and the accountability of Parliament to the electorate are diminished. Moreover, there is a real risk that, notwithstanding a judicial gloss which renders less draconian or saves from invalidity a provision of a statute, the provision will be administered according to its ordinary, apparent and draconian meaning."
There is a further reason why a court should resist being drawn into adopting a strained meaning of a statute when it is merely to sidestep or minimise the prospect of constitutional invalidity. That reason was well articulated in a recent critique of the practice of construing statutes to avoid constitutional doubt in the Supreme Court of the United States. The reason is that the facility merely to express constitutional doubt as the basis for making a constructional choice "allows judges to articulate constitutional principles in a context where the real impact of those principles - the invalidation of a law - will be unfelt" in a manner that "is anomalous in a case-or-controversy legal system that (ostensibly) abhors advisory opinions". To construe a statute to avoid not a judicial determination of invalidity but a judicially articulated doubt as to validity "is problematic because it unmoors adjudication from the traditional, structural source of judicial restraint".
Only if each were reasonably open in the application of ordinary principles of statutory construction could the prospect of constitutional validity or invalidity legitimately bear on the choice between competing constructions; and only then if the court were satisfied that one construction would lead to validity and the other to invalidity.
I am unable to accept that the defendant's construction of s 133AB(2)(a) is reasonably open in the application of ordinary principles of statutory construction.
The proper construction is to be found in the meaning of the statutory language, read in its statutory context and in light of its statutory purpose. The principle of construction known as the principle of legality is of little assistance given that the evident statutory object is to authorise a deprivation of liberty and that the statutory language in question is squarely addressed to the duration of that deprivation of liberty. The principle "exists to protect from inadvertent and collateral alteration rights, freedoms, immunities, principles and values that are important within our system of representative and responsible government under the rule of law", and "is fulfilled in accordance with its rationale where the objects or terms or context of legislation make plain that the legislature has directed its attention to the question of the abrogation or curtailment of the right, freedom or immunity in question and has made a legislative determination that the right, freedom or immunity is to be abrogated or curtailed". The principle provides no licence for a court to adjust the meaning of a legislative restriction on liberty which the court might think to be unwise or ill-considered.
Focusing on the statutory language, the defendant's construction involves a distortion, not just of the words of s 133AB(2)(a) but of the opening words of s 133AB(3). The conferral of authority on a member of the Police Force to "hold the person for a period up to 4 hours" is not on its face purposively related to the power of that member or another member to deal with the person. The conferral of authority to deal with the person "on the expiry" of the period of detention rather indicates that the authority to deal with the person is separate from, and sequential to, the authority to detain. What it also indicates is that the expiration of the period of detention must be capable of being ascertained before the authority to deal with arises. The expiration of the period of detention triggers the exercise of the authority to deal with, not the other way round.
Looking more broadly to the statutory context, there exists on any view a tension between: the specific authority conferred by s 133AB(2)(a) on a member of the Police Force to detain a person the member has taken into custody after arresting the person without warrant under s 123 for an infringement notice offence; and the general requirement of s 137(1) for any person who is taken into custody to be brought before a justice or a court of competent jurisdiction as soon as is practicable after being taken into custody. The resolution of that tension necessarily involves determining "which is the leading provision and which the subordinate provision, and which must give way to the other".
The natural reconciliation of the two provisions lies in the identification of s 133AB(2)(a) as a specific provision which takes temporal precedence over the general requirement of s 137(1) in relation to a person arrested and taken into custody for an infringement notice offence. The general requirement of s 137(1) has application to such a person only after the period of detention for which s 133AB(2)(a) provides has expired, and only in the event of a member of the Police Force deciding to deal with the person in accordance with the option provided by s 133AB(3)(d). The whole of s 137 then operates in accordance with its terms, ordinarily to require compliance with that requirement by the soonest practicable time after a person is taken into custody, but to permit of extension for such period as is reasonable to enable the person to be questioned or for investigations to be carried out to obtain evidence of, or in relation to, an offence which involves the person.
The reconciliation of the two provisions is more problematic on the defendant's construction. On that construction, s 137(1) would always operate in relation to a person arrested and taken into custody for an infringement notice offence so as immediately to require that person to be brought before a justice or a court as soon as practicable after being taken into custody under s 133AB(2). The authority granted by s 133AB(2)(a), to detain the person for up to four hours, would be recast so as to operate as nothing more than a qualification to that requirement of s 137(1). Given that s 137(1) would already have been engaged from the moment of the person having been taken into custody, s 137(1) would not need to be engaged in the event of a member of the Police Force deciding to deal with the person in accordance with the option provided by s 133AB(3)(d). Yet s 137(1) would somehow be disengaged in the event of a member of the Police Force deciding to deal with the person in accordance with any of the other three options provided by s 133AB(3).
In interpreting a provision of a Northern Territory Act, including a part of a Northern Territory Act, "a construction that promotes the purpose or object underlying the Act (whether the purpose or object is expressly stated in the Act or not) is to be preferred to a construction that does not promote the purpose or object". Moreover, in interpreting a provision of a Northern Territory Act, including again a part of such an Act, "if material not forming part of the Act is capable of assisting in ascertaining the meaning of the provision, the material may be considered … to confirm that the meaning of the provision is the ordinary meaning conveyed by the text of the provision taking into account its context in the Act and the purpose or object underlying the Act". Extrinsic material "cannot be determinative; it is available as an aid to interpretation". Extrinsic material does not displace the text but can illuminate the meaning conveyed by the text.
The defendant's construction relies on confining the statutory purpose of Div 4AA to the narrow purpose of resolving what is said to be pre-existing ambiguity as to the ability of a member of the Police Force, consistently with s 137, to release a person arrested without warrant under s 123 while issuing an infringement notice to that person. Were that the only purpose, it would be difficult to see why Div 4AA was enacted in such an elaborate form and why s 133AB(2) was enacted at all.
The true and much broader purpose of Div 4AA was that spelt out by the Attorney-General for the Northern Territory at the time of the introduction in the Legislative Assembly of the Bill for its enactment. The Attorney-General then said:
"The purpose ... is to provide members of the Northern Territory Police Force with an alternative post-arrest option, where a person who has committed certain prescribed offences may be held by police for up to four hours and can then be released with an infringement notice, as opposed to requiring that the person be charged and have those charges be heard by a court. I will refer to the concept as 'paperless arrest'.
... The policy is to permit police officers to detain individuals for up to four hours in relation to public order-type offences, and where an infringement notice may be issued. ...
This alternative post-arrest option will provide further flexibility and efficiency in policing work. The option will enable police officers to return to their patrol in a more timely fashion, as opposed to being detained for long periods preparing necessary paperwork for a court to consider the charges. An additional benefit to the community is intended by the use of such an option to de-escalate social disorder situations or potential situations of public disorder before they escalate into major incidents."
The Attorney-General went on later during the debate on the Bill in the Legislative Assembly to describe Div 4AA as giving members of the Police Force "a vehicle by which to remove [summary offenders], contain them and then release them". He described it as "a form of catch and release". The Attorney-General said:
"This system simply restores a simple idea that when a police officer arrests a person for a street offence, they have taken that person out of commission. They bring them to the watch house, drop them off at the watch house, write out the summary infringement notice - so it is not entirely paperless - which goes into the property bag of the person who is then placed in the cells for the next four hours. In four hours' time, they come out, collect their property, collect their summary infringement notice, and if they wish to contest the allegations in the summary infringement notice, then there are processes for that to occur. Those processes are explained on the back of the summary infringement notice.
This means the police will no longer become arrest averse. It will actually say to the police that if these clowns are playing up, arrest them, take them into custody, get them out of circulation."
The plaintiffs' construction not only fits the statutory language of s 133AB, but fits that identified statutory purpose of Div 4AA. It gives to s 133AB and s 137 a natural sequential operation in relation to persons taken into custody following arrest without warrant for infringement notice offences. It does so by giving s 137 full operation where those persons are dealt with at the expiration of their detention in accordance with s 133AB(3)(d). It should be accepted.
On its proper construction, s 133AB(2)(a) authorises a member of the Police Force to detain a person arrested and taken into custody for an infringement notice offence for any period up to a maximum of four hours. The period of detention, up to that maximum period of four hours, is left to the discretion of the member.
That discretion as to the period of detention is not unconfined: undoubtedly, it is to be exercised in good faith and for a proper (that is to say, non-extraneous) purpose, which might permissibly be as broad as the maintenance of social order. The discretion is nevertheless undefined. It is not constrained to be exercised so as to ensure that the person is detained only for such time as is reasonable or practicable to enable the person to be brought before a justice or a court of competent jurisdiction or to enable the person to be dealt with in another way permitted by law. Nor is the discretion constrained to be exercised only in a manner which ensures that the detention is protective of the person or of other persons or preventive of harm.
It is necessary now to face up to the constitutional consequences of that construction.
Characterisation
The starting point for constitutional analysis is the frequently repeated observation in the joint reasons for judgment in Chu Kheng Lim v Minister for Immigration, Local Government and Ethnic Affairs that, "exceptional cases" aside, "the involuntary detention of a citizen in custody by the State is penal or punitive in character and, under our system of government, exists only as an incident of the exclusively judicial function of adjudging and punishing criminal guilt". The observation has its foundation in the concern for the protection of personal liberty lying at the core of our inherited constitutional tradition, which includes the inheritance of the common law. Liberty is "the most elementary and important" of those basic common law rights, which "traditionally, and therefore historically, are judged by that independent judiciary which is the bulwark of freedom".
The centrality of personal liberty to the functioning of government within our 800 year old inherited tradition was captured in the still frequently cited eighteenth century prose of Sir William Blackstone:
"Of great importance to the public is the preservation of this personal liberty: for if once it were left in the power of any, the highest, magistrate to imprison arbitrarily whomever he or his officers thought proper ... there would soon be an end of all other rights and immunities. ... To bereave a man of life, or by violence to confiscate his estate, without accusation or trial, would be so gross and notorious an act of despotism, as must at once convey the alarm of tyranny throughout the whole kingdom. But confinement of the person, by secretly hurrying him to gaol, where his sufferings are unknown or forgotten; is a less public, a less striking, and therefore a more dangerous engine of arbitrary government."
Explaining the protection of personal liberty which the common law provided, Blackstone continued:
"To make imprisonment lawful, it must either be, by process from the courts of judicature, or by warrant from some legal officer, having authority to commit to prison; which warrant must be in writing, under the hand and seal of the magistrate, and express the causes of the commitment, in order to be examined into (if necessary) upon a habeas corpus. If there be no cause expressed, the [gaoler] is not bound to detain the prisoner. For the law judges in this respect ... that it is unreasonable to send a prisoner, and not to signify withal the crimes alleged against him."
The joint reasons in Lim specifically acknowledged, as the "most important" of the exceptional cases in which involuntary detention has been accepted not to be penal or punitive in character, "the arrest and detention in custody, pursuant to executive warrant, of a person accused of crime to ensure that he or she is available to be dealt with by the courts", noting that "the power to detain a person in custody pending trial is ordinarily subject to the supervisory jurisdiction of the courts". The common law facilitated the exercise of that supervisory jurisdiction by imposing a requirement, replicated in s 137(1), that a person arrested be brought before a justice or a court as soon as is practicable after being taken into lawful custody.
The joint reasons in Lim also acknowledged that the exceptional circumstances in which involuntary detention might not be penal or punitive would include cases of detention under mental health legislation and detention under quarantine legislation. Other limited forms of protective or preventive detention might well be envisaged. Cases subsequent to Lim have illustrated the difficulty of seeking to draw a bright-line distinction between penal or punitive detention and protective or preventive detention. The difficulty of drawing any distinction between detention which is penal or punitive and detention which is not highlights the significance of default characterisation: any form of detention is penal or punitive unless justified as otherwise. The question is always one of characterisation of the detention, in respect of which the object sought to be achieved by the law authorising detention is a relevant consideration, but not the only consideration.
More recent cases indicate that no form of executive detention in the exercise of a statutory power to detain can escape characterisation as punitive unless the duration of that detention meets at least two conditions. The first is that the duration of the detention is reasonably necessary to effectuate a purpose which is identified in the statute conferring the power to detain and which is capable of fulfilment. The second is that the duration of the detention is capable of objective determination by a court at any time and from time to time.
The detention that is authorised by Div 4, of a person who a member of the Police Force has reasonable grounds for believing is intoxicated, can readily be seen to satisfy both of those conditions. So too can the detention that is authorised by s 137(2) or (3), of a person who has been arrested and taken into custody, for such period as is reasonable to enable the person to be questioned, or investigations to be carried out to obtain evidence of, or in relation to, an offence which involves the person.
The detention that is authorised by Div 4AA plainly satisfies neither of those conditions. The duration of the detention within the four hour maximum specified in s 133AB(2)(a) is not limited by reference to the time needed to effectuate any identified statutory purpose, and the duration of that detention within the four hour maximum is designedly left to the discretion of a member of the Police Force. The duration of the detention depends on the choice of the member as to how long to take a person out of circulation.
Moreover, the detention that is authorised by Div 4AA is detention of a person whom the member of the Police Force has arrested on the basis that the member believed, albeit on reasonable grounds, that the person had committed, was committing or was about to commit an offence. It is a form of detention which results from the member acting not as an accuser but as a judge.
This is not an occasion to mince words. The form of executive detention authorised by Div 4AA is punitive. Because it is punitive, the imposition of the detention involves the exercise of a function which our constitutional tradition treats as pertaining exclusively to the exercise of judicial power.
Separation of powers
The doctrine of separation of powers enshrined in Ch III of the Constitution has its principal textual anchor in the opening words of s 71. Those words are that "[t]he judicial power of the Commonwealth shall be vested in ... the High Court of Australia, and in such other federal courts as the Parliament creates, and in such other courts as it invests with federal jurisdiction". The doctrine ascribes to those words an allocation of the judicial power of the Commonwealth which is both exclusive and exhaustive. The Parliament of the Commonwealth can vest judicial power of the Commonwealth only in courts referred to in s 71, and the Parliament can vest in those courts only judicial power of the Commonwealth or power incidental to judicial power of the Commonwealth.
Division 4AA has not been enacted by the Parliament of the Commonwealth. It has been enacted by the Legislative Assembly in the exercise of a distinct legislative power to make laws for the peace, order and good government of the Territory. That distinct legislative power was conferred on the Legislative Assembly in the exercise by the Parliament of its power under s 122 of the Constitution to "make laws for the government of any territory". The exercise by the Legislative Assembly of that distinct legislative power, although derived from the Parliament, "is not an exercise of the Parliament's legislative power".
When they argue that Div 4AA infringes the doctrine of separation of powers enshrined in Ch III of the Constitution, the plaintiffs necessarily argue that the judicial power which is conferred by a law enacted in the exercise of a distinct legislative power conferred by the Parliament under s 122 is judicial power of the Commonwealth.
That premise of the plaintiffs' argument was considered and rejected in Kruger v The Commonwealth. To a question asking whether a Territory law which authorised executive removal and confinement of persons was invalid on grounds (amongst others) that "it purported to confer judicial power of the Commonwealth ... on persons who were not appointed under or obliged or entitled to exercise the judicial power of the Commonwealth in accordance with Ch III of the Constitution", the formal answer of the Court was "No". Each of the four Justices constituting the majority who joined in that answer adopted reasoning which involved a rejection of the proposition that judicial power invested by a law enacted in the exercise of legislative power conferred under s 122 is judicial power of the Commonwealth.
The question as now reframed in this special case cannot be approached as if it had not been answered before. What needs to be addressed is not how the question might best be answered if the historical slate were to be wiped clean and the Constitution were to be read anew, but whether there is sufficient justification for now reopening, and, if so, departing from the answer already given in, Kruger.
How s 122 relates to Ch III is "a problem of interpretation ... which has vexed judges and commentators since the earliest days of Federation". "It would have been simple enough ... to hold that the courts and laws of a Territory were federal courts and laws made by the Parliament." Equally, it would have been simple enough to treat s 122 as wholly divorced from Ch III so as to be entirely "disparate and non-federal". The first of those simple approaches has never commanded assent, and the second (although it acquired early ascendancy) can no longer be accepted in unqualified terms. It has been held, for example, that s 76(ii) operates in conjunction with s 77(i) to permit the Parliament to confer jurisdiction on federal courts in matters arising under laws made under s 122. The jurisdiction conferred on a federal court by a law made by the Parliament can only be federal jurisdiction. And although a negative answer has now repeatedly been given to the question whether a Territory court is a federal court subject to s 72, it has been emphasised that the negative answer which has so been given is "not to a wide question as to the relationship between Ch III and s 122".
The answer given in Kruger to the wide question as now reframed in this special case cannot be said to have involved no difference between the reasoning of the justices who constituted the majority, or to have rested on a principle carefully worked out in a succession of cases. On the other hand, there cannot be said to be anything in the cases decided before Kruger which lends support to the different answer that the plaintiffs now seek. The plaintiffs fairly acknowledge that two of them, Spratt v Hermes and Capital TV and Appliances Pty Ltd v Falconer, stand against acceptance of that answer.
The most significant development to have occurred since Kruger has been the recognition in North Australian Aboriginal Legal Aid Service Inc v Bradley that Territory courts, no less than State courts, answer the description in s 71 of courts which the Parliament can invest with federal jurisdiction and which are capable of exercising the judicial power of the Commonwealth by reason of that investiture. The result is that federal jurisdiction can be invested by the Parliament in a Territory court under s 122 as well as in a State court under s 77(iii).
The plaintiffs seek to go further than Bradley. They seek to advance an argument to the effect that all jurisdiction exercised by a Territory court is federal jurisdiction, at least where the matter to be adjudicated concerns rights or liabilities which owe their existence to a law made by the Parliament under s 122. The strongest form of an argument to that effect was developed with conspicuous clarity in the academic writing of Professor Zines. The argument as so developed builds on the settled understanding that the description in s 76(ii) of a matter arising under a law made by the Parliament extends to a matter in which a right or duty in issue owes its existence to a law made by the Parliament. Such an argument would then go on, of necessity, to rely on a more contestable proposition: that a matter is sufficiently described as a matter in federal jurisdiction if the matter answers the description of one or more of the nine matters referred to in ss 75 and 76, irrespective of the source of authority to adjudicate that matter.
The argument has significant implications for the scope of the appellate jurisdiction of the High Court under s 73 and, in consequence, for whether it might be possible in Territories (although it is impossible in States) to "create islands of power immune from supervision and restraint". Acceptance of the argument would lead to rejection of the conclusion in Capital TV and Appliances Pty Ltd v Falconer that no appeal lies to the High Court from a Territory court under s 73 of the Constitution. Acceptance of the argument would also involve rejection of reasoning in Spratt v Hermes to the effect that a Territory court did not exercise federal jurisdiction when it heard a prosecution for an offence against a Commonwealth law at a time before the amendment in 1976 of s 68(2) of the Judiciary Act 1903 (Cth) specifically to confer federal jurisdiction on Territory courts in the same way as it confers federal jurisdiction on State courts. The argument need not be considered now.
The argument, if accepted, would not take the plaintiffs the whole of the distance they need to travel. Section 71, it is to be recalled, relevantly refers to the judicial power of the Commonwealth as being vested in such courts as the Parliament invests with federal jurisdiction. To accept that all jurisdiction exercised by a Territory court is federal jurisdiction would not be to accept that all federal jurisdiction exercised by a Territory court is federal jurisdiction vested in that court by the Parliament, so as to involve the exercise of judicial power of the Commonwealth within the meaning of s 71. It therefore would not follow, from acceptance that all jurisdiction exercised by a Territory court is federal jurisdiction, that any judicial power conferred by a Territory law is judicial power of the Commonwealth.
The reasoning in Bradley is in truth opposed to the notion that judicial power conferred by a Territory law is judicial power of the Commonwealth. The first of the propositions accepted in Bradley was that "a court of the Territory may exercise the judicial power of the Commonwealth pursuant to investment by laws made by the Parliament". It was not that a court of the Territory might exercise the judicial power of the Commonwealth pursuant to investment by laws made by a legislature of a Territory. That first proposition then formed the foundation for the holding in Bradley that the doctrine associated with Kable v Director of Public Prosecutions (NSW) applies to Territory courts in the same way as it applies to State courts. That holding would be redundant if the doctrine of separation of powers were applicable.
The actual result in Bradley has also removed much of the force of the apparent incongruity of Territory courts being distinct from federal courts, and of Territory judicial power being discrete from Commonwealth judicial power. By equating Territory courts with State courts for the purpose of s 71 of the Constitution, Bradley subjects the legislatures of self-governing Territories to the same strictures as Ch III of the Constitution applies to the Parliaments of the States. The result is to afford to citizens resident in Territories the derivative constitutional protection provided by Ch III in no lesser degree than is afforded to citizens resident in States.
Bradley has stood for more than a decade, and Kruger has stood for nearly two decades. Their holdings are consistent. Given that the doctrine of separation of powers has implications for institutional design which extend well beyond considerations of personal liberty, it cannot be said that Kruger has achieved no useful result or has led to inconvenience. Kruger has been acted on by Territory legislatures to establish institutional structures, blending judicial and non-judicial power, broadly equivalent to those which exist in most States.
Kruger should not be reopened. The legislative power of the Legislative Assembly is not constrained by the doctrine of separation of powers enshrined in Ch III of the Constitution. Division 4AA therefore cannot infringe that doctrine. But that is not the end of the analysis.
Institutional integrity
Bradley explained the doctrine associated with Kable, in its application to State courts and Territory courts alike, to rest on the proposition "that it is implicit in the terms of Ch III of the Constitution, and necessary for the preservation of that structure, that a court capable of exercising the judicial power of the Commonwealth be and appear to be an independent and impartial tribunal". Underlying that proposition is an understanding that "[a] State or Territory law that undermines the actuality or appearance of a State or Territory court as an independent and impartial tribunal is incompatible with Ch III because it undermines the constitutionally permissible investiture in that court of the separated judicial power of the Commonwealth".
Bradley demonstrated independence and impartiality to be defining characteristics of a court capable of exercising the judicial power of the Commonwealth. Decisions before and after have emphasised that independence and impartiality do not exhaust those defining characteristics. In Fardon v Attorney-General (Qld), the essential concern of the doctrine, and the touchstone for its application, was identified as the protection from legislative impairment of the "institutional integrity" of courts: that is to say, the protection of the integrity of courts as institutions established for the administration of justice.
Thus, as was explained in Forge v Australian Securities and Investments Commission, with reference to Kable, Fardon and Bradley:
"[T]he relevant principle is one which hinges upon maintenance of the defining characteristics of a 'court' ... It is to those characteristics that the reference to 'institutional integrity' alludes. That is, if the institutional integrity of a court is distorted, it is because the body no longer exhibits in some relevant respect those defining characteristics which mark a court apart from other decision-making bodies."
The explanation in Forge continued by emphasising that "[i]t is neither possible nor profitable to attempt to make some single all-embracing statement of the defining characteristics of a court". Institutional attributes can too readily be taken for granted until such time as they are seen to come under threat.
The principle as explained in Forge operates to invalidate a State or Territory law which confers on a State or Territory court "a power or function which substantially impairs the court's institutional integrity, and which is therefore incompatible with that court's role as a repository of federal jurisdiction". Yet the operation of the principle is not confined to invalidating a law by reference to impairment of institutional integrity in the nature or manner of exercise of a power or function which the law confers on a court.
Cases in which the principle has been applied to hold State laws invalid have included those in which impairment of the institutional integrity of a court has been seen to arise from the nature of the task which a court was required to perform. They have also included cases in which impairment of the institutional integrity of a court has been seen to arise from the nature of the incidents of a function conferred on a person, rather than a court, and by reference to the position in which a court is placed within an overall legislative scheme.
The cases show that a tendency to undermine public confidence in a court is indicative of a law which impairs the institutional integrity of that court. They show that the character of a law as impairing the institutional integrity of a court can also be indicated by a legislative plan which builds on public confidence in that court to bolster what is essentially legislative or executive action, so as metaphorically "to cloak their work in the neutral colors of judicial action".
In Kable itself, both of those tendencies combined in legislation seen to conscript a court in a legislative plan for the procurement of the continuing imprisonment of an identified individual after the expiration of the sentence which had earlier been imposed by a court for the crime of which he was convicted. The proposition that punitive detention ordinarily exists under our system of government only as a consequence of the judicial adjudication of criminal guilt, as expounded in Lim, was reflected in the reasoning of members of the majority in concluding that the institutional integrity of the court was impaired.
The reasoning in Kable was complex. So has been the reasoning in some of the cases which have applied it. Multiple factors have been in the mix.
But a doctrine which has its foundation in the protection of the integrity of courts as institutions for the administration of justice need not always be difficult to apply. Not every case is one of complexity. And incompatibility with the institutional integrity of a court can arise quite irrespective of considerations of public confidence.
A law which confers a power or function on a court which is "repugnant to the judicial process in a fundamental degree" is a law which is for that reason alone incompatible with the institutional integrity of that court. A law which gives to a court a role in a legislative scheme designed to facilitate punitive executive detention must surely be within the same category. The role is antithetical to the existence of the court as an institution for the administration of justice; repugnant in a fundamental degree to the judicial status.
Courts are defined as much by what they don't do as by what they do and how they do it. Implicit in a tradition which reserves punitive detention presumptively to the judicial power is an understanding that punitive detention imposed in the exercise of judicial power is in consequence of adjudication by a court acting in accordance with a judicial process. Part of what sets courts apart from other institutions within our system of government is that they do not participate in a punitive deprivation of liberty by another arm of government.
The plaintiffs place understandable emphasis, in their argument that Div 4AA impairs the institutional integrity of courts of the Northern Territory, on the lack of any involvement on the part of those courts in the instigation or supervision of the detention for which s 133AB(2)(a) provides. Acknowledging that there is no ousting of the jurisdiction of the Supreme Court to ensure that any detention remains within the limits set by s 133AB(2)(a), they emphasise that the detention allowed to occur within those legislated limits is entirely in the exercise of executive discretion.
That emphasis is well placed to the extent of highlighting the executive detention authorised by Div 4AA as punitive. For reasons I have already set out at some length, I have concluded that the detention is properly characterised as punitive.
That being the character of the detention, the problem with Div 4AA from the perspective of the protection of the institutional integrity of courts of the Northern Territory arises not from those courts being kept out of the process of punitive detention for which s 133AB(2)(a) provides. The problem rather arises from those courts being brought into the further processes which Div 4AA contemplates will occur after that period of punitive detention is over.
The constitutional flaw in the design of Div 4AA lies in the role which it gives to Territory courts in the options from which a member of the Police Force must choose under s 133AB(3) when deciding how to deal with the person detained at the end of the period of punitive detention which that member or another member of the Police Force has imposed under s 133AB(2)(a). It is only the first of those options - unconditionally releasing the person in accordance with s 133AB(3)(a) - which does not involve, or cannot give rise to, the commencement of proceedings for the prosecution of that person in the Court of Summary Jurisdiction, with a consequent right to appeal to the Supreme Court. The result of any prosecution which will occur if the person is dealt with under s 133AB(3)(b), (c) or (d) will be an adjudication which determines the criminal liability of the person. Whatever the outcome of that adjudication, the person will already have been punished through the executive detention that has occurred. No subsequent action by a court can change that historical fact.
Courts of the Northern Territory are thereby made support players in a scheme the purpose of which is to facilitate punitive executive detention. They are made to stand in the wings during a period when arbitrary executive detention is being played out. They are then ushered onstage to act out the next scene. That role is antithetical to their status as institutions established for the administration of justice.
Lest it be thought incongruous that the constitutional defect in a legislative scheme of punitive executive detention is to be found at the periphery of that detention, in the subsidiary role which the legislative scheme gives to courts, it is important to recognise that a constitutional doctrine which limits legislative design has flow-on effects for political accountability. Were the provisions which contemplate a role for courts to be removed, the legislative scheme of Div 4AA would appear to be quite different. The legislative scheme would be starkly one of catch and release. The scheme would be reduced so as to appear on the face of the legislation implementing it to be one which authorises police to detain, and then release, persons arrested without warrant on belief of having committed or having been about to commit an offence. The political choice for the Legislative Assembly would be whether or not to enact a scheme providing for deprivation of liberty in that stark form.
Conclusion
The questions asked in the special case should be formally answered as follows: