SLICER J The applicant was convicted of the offences of assaulting a police officer acting in the execution of his duty contrary to the Police Offences Act ("the Act"), s34B(1)(a)(i) and threatening the same officer contrary to the Act, s34(1)(b).

2. There was no issue that he had struck the officer and used the words constituting the offences. The issue was whether or not the officer was, at the relevant time, acting in the execution of his duty. The sole ground of the motion to review was:

"The learned magistrate erred in law in deciding that as

between the defendant and the police officer, the police

officer was acting in the execution of his duty."

3. A police officer, while on routine patrol, observed a group of persons, one of whom he believed to be subject to an outstanding warrant for the non-payment of a fine. He spoke to the young man, the son of the applicant, but was falsely told by him that he was the twin brother of the person subject to the warrant. Shortly thereafter, seeing the twin brother at the rear of the licensed premises where he had sighted the first youth, he realised that he had been deceived and returned to the original group, where in his words:

"... noticed an altercation up the street ... and

alighted from the vehicle and went towards Scott Smith

and informed him that he was under arrest for the

altercation and at the same point in time I took hold of

him with my right hand ..."

and in further elaboration: "... where I informed Scott

that he was under arrest for the offence which I

detected, and also I believe that in fact he was Scott

Smith and I was in possession of commitment warrants ...

and I intended to execute them, the altercation then

developed into a family altercation where I had other

members of the family actually push between me and the

person I had arrested, the defendant became quite

verbally abusive towards me ... threatening that if he

could get to me ..."

and that after about a minute: "... I noticed Paul Smith

(the applicant) .. within three to four feet and (he)

threw that can of beer at me, and he struck me in the

left leg between the knee and the thigh."

4. At the time he was struck he averred that he had hold of Scott Smith and was attempting to move him back to the police vehicle. The applicant was not arrested and proceedings were commenced against him some 11 days later.

5. The learned magistrate held that the officer was not entitled to arrest Scott Smith by reason of the existence of a warrant since, in his view, "at common law the execution of the warrant will be unlawful if the arresting officer does not have the warrant with him, ready to be produced if required".

6. No issue was taken by either the applicant or the respondent with that ruling.

7. In relation to the claim that Scott Smith had been arrested because of the altercation, the learned magistrate expressed himself to be dubious as to the professed reason advanced by the officer, and paying regard to other evidence, including the absence of corroboration by another police officer, found that:

"On that issue I am not satisfied beyond reasonable doubt

the arrest was lawful, that is, I am not prepared to

conclude beyond reasonable doubt that the defendant's son

was fighting with another person and that he was arrested

for anything other than the warrant or warrants."

- that the officer was acting in the execution of his

duty by attempting to convey an arrested person to the

police station for the purpose of the laying of a charge;

- that the applicant was entitled to assist his son if

the arrest was unlawful;

- that the applicant was not attempting to assist his son

and his conduct evidenced no "constructive purpose"; and

- that as between the defendant and the police officer

"the police officer was acting in the execution of his

duty".

9. The learned magistrate did not set out the basis of these conclusions but referred to the reasoning he had adopted (and the authorities relied on for such reasoning) in his earlier decision in Wood v Rouse, magistrate's decision 10/1990.

10. In the case of Wood v Rouse (supra) the magistrate was determining the prosecution of a person arrested for loitering. Whilst in custody the person had assaulted an officer. The charge of loitering was not proceeded with, there being little factual evidence to support the charge. Applying the reasoning stated by the House of Lords in Christie v Leachinsky [1947] UKHL 2; (1947) AC 573 his Worship found that the defendant was lawfully in custody at the time of the assault. He further concluded, having considered the authorities of The Queen v Kulynycz (1970) 3 All ER 881 and Miller v Noblet (1927) SASR 385 that:

- a later notification (of the correct basis for arrest)

could cause the custody to be lawful from the time of

notification;

- it mattered not that a different charge was ultimately

preferred;

- if an officer makes an error in effecting an arrest

"the remedy cannot be that the officer must let the

arrestee go free"; and that

- "once a police officer makes an arrest, lawful or not,

he has a broader duty with which he has then acting in

accordance: namely to convey his prisoner promptly to a

police station so that his superior can act in accordance

with law" (eg Justices Act 1959, s34).

11. The issue is whether the constable was, at the time of the assault and the use of threatening language, acting in the lawful execution of his duty. It is not whether he was so acting vis-a-vis the applicant. It is not whether he could avail himself of a defence to an action for wrongful arrest or detention. For example, in an action for wrongful arrest it may be necessary for the party to establish malice. See Coulson v Huddlestone, Tas unreported 80/1967. It is not whether the applicant could have been arrested for assault simpliciter or convicted of that offence.

12. A police officer may lawfully arrest a person if he, the police officer, believes, on reasonable grounds, that the person has committed an arrestable offence. He may arrest, with warrant, in respect of some offence and for others without warrant. He is entrusted by society with special powers by virtue of statute and common law. He may not arrest without power nor act on capricious grounds. The test of what constitutes "reasonable grounds" is not dependent on the subjective belief of the constable. Nor is it dependent on whether, at the end of the day, there exist sufficient evidence to warrant a conviction.

13. A mistaken belief of itself does not permit the constable to exercise the power of arrest. See Davis v Lisle (1936) 2 KB 434.

14. An arrest on reasonable grounds which was subsequently found to be mistaken could nevertheless be lawful. A reasonable but mistaken arrest does not involve the conclusion that the officer is liable in damages. There is a distinction between the conduct of a constable being justified as a shield to a civil action and his status being used as a sword with which a further offence can be created.

15. As was stated in Christie v Leachinsky (supra) at 592-593:

"... an arrest does not become wrongful merely because

the constable arrests a man for one felony, say murder,

and he is subsequently charged with another felony, say

manslaughter. It is not enough to say that in such a

case the accused man could not recover any damages in an

action for false imprisonment. It is more than that. It

is clear that the constable has not been guilty of an

illegal arrest ... Nor again, can it be wrongful to

arrest and detain a man upon a charge, of which he is

reasonably suspected, with a view to further

investigation of a second charge upon which information

is incomplete. In all such matters a wide measure of

discretion must be left to those whose duty it is to

preserve the peace and bring criminals to justice."

16. That statement is not authority to enable arrest without cause. It requires a test of reasonableness. It requires substance rather than a formula of words. It requires meaning not ritual.

17. It is significant that the Act, s34B itself prescribes as a precondition to the exercise of the power of arrest without warrant that the officer was effecting a lawful arrest in that s34B(1)(a)(iii) states:

"34B - (1) A person shall not -

(a) assault, resist, or wilfully obstruct -

...

(iii) a person lawfully arresting another person;

...

(3) A police officer may arrest without warrant any

person committing an offence against subsection (1) or

(2)(a)."

18. It would be anomalous if Parliament prohibited an arrest under subs(iii) in circumstances where the arrest was unlawful, yet permitted an arrest for the same act by reason of subs(1)(a)(i) (a police officer acting in the execution of his duty). It is true that subs(1)(a)(iii) protects persons of a class wider than police officers but it is inclusive of them.

19. In Innes v Weate (1984) Tas R 14 Cosgrove J considered the powers of police officers and their status as persons able to intervene in the interests of the community. He said at 19-20:

"When circumstances occur which call upon a constable qua

constable to intervene in the interests of the community

his power to do so comes from a different source and has

different consequences. A constable on duty is

representative of the community, at large, and his duty

is to the community, not to any one citizen. The courts,

while recognizing that, as such a representative, he is

invested with a wide discretion, have never been slow to

restrain his actions in the interests of liberty, and

confine the exercise of the discretion to intervene to

cases where such intervention is properly called for and

reasonably carried out. The legislature also has

carefully scrutinised the authority of constables,

sometimes extending it, sometimes narrowing it. The duty

of constables arises from the law and is circumscribed by

it. No citizen, corporation, or arm of the State, no

matter now politically powerful, can simply by making a

request for assistance, impose a duty on a constable to

give that assistance. Nor can a constable invest himself

with a duty to assist one party in a civil dispute on the

sole ground that, in his judgment, that party has civil

right on his or its side, or ought, for political

reasons, be granted assistance."

20. In the event that there is a finding that there was no or not sufficient evidence to establish the existence of a disturbance, it could not be said that there existed reasonable grounds for the effecting of a lawful arrest. See Falvey v Burns (1939) St R Qd 217.

21. It may be that a custody officer acts in the lawful execution of his duty when dealing further with a person unlawfully arrested since he is required by separate legal power to undertake further duties with respect to that prisoner. It may be that a person attempting to rescue the prisoner from the custody of that officer could be held liable for an assault on that officer acting in the execution of duty. But the "execution of duty" would have arisen from a specific statutory responsibility entrusted to that officer not from the status of the arrest. In this case no such question arises.

22. In this case the finding of the magistrate precludes any question of whether or not the arrest could be regarded as having been reasonably effected. The constable possessed no power to arrest Scott Smith with respect to the outstanding warrant. He did not have it in his possession and could not execute it. The magistrate found that the altercation claimed by the constable to give rise to power did not occur. It could not then clothe the constable with "reasonable grounds". The finding did not afford a conclusion that there had been a mistake (as, for example, who was fighting or whether or not someone was acting in lawful self-defence) albeit a reasonable one. The constable simply did not have the power of arrest. It could not be said that at the time of the conduct of the applicant the constable was acting in the execution of duty.

23. The motion to review will be upheld. The order of the magistrate convicting the applicant and the sentencing to a term of imprisonment for one month is set aside. There is no reason to remit the matter to the learned magistrate for further determination. ORDERS

1 The motion to review is upheld.

2 The convictions of the applicant with respect to

complaint No 60621/93 are set aside.

3 The charges of offences contrary to the Police Offences

Act 1935, s34B(1)(a)(i) and (b) comprised in complaint No

60621/93 are dismissed.