1. the existing percentage of care determination of 0% to the Father is revoked from 3 February 2022 and replaced with a new percentage of care determination of 50% applying from 4 February 2022; and

1. the existing percentage of care determination of 100% to the Mother is revoked from 3 February 2022 and replaced with a new percentage of care determination of 50% applying from 4 February 2022.

The Tribunal determines pursuant to section 87AA of the Child Support (Registration and Collection) Act 1988 that section 87AA applies as if the reference to 28 days in paragraph 87AA(1)(b) was a reference to a longer period extending until 7 December 2022.

Names used in all second review child support published decisions are pseudonyms. Any references appearing in square brackets indicate that information has been removed from this decision and replaced with generic information so as not to identify involved individuals as required by sections 16(2AB)-16(2AC) of the Child Support (Registration and Collection) Act 1988.

CHILD SUPPORT - care percentage determination - whether pre-existing percentages of care to be revoked - pattern of care - inconsistent evidence - minor departures from pattern of care - whether special circumstances prevented objection being lodged within 28 days

Administrative Appeals Tribunal Act 1975 (Cth)

Administrative Review Tribunal (Consequential and Transitional Provisions No. 1) Act 2024 (Cth)

Child Support (Assessment) Act 1989 (Cth)

Child Support Registrar v BKCZ [2023] FCA 1109

MDXJ v Secretary, Department of Social Services [2121] FCA 1767

Hneidi v Minster for Immigration and Citizenship [2110] FCAFC 21: (2110) [2010] FCAFC 20; 182 FCR 115

Minister for Home Affairs v G [2119] FCAFC 79; (2119) [2019] FCAFC 79; 266 FCR 569

Re Drake and Minister for Immigration and Ethnic Affairs (No 2) (1979) 2 ALD 634

Department of Social Services, Child Support Guide (Guides to Social Policy Law, version 4.91, 1 July 2025)

1. Mr BRDF (the Father) and Ms KCDR (the Mother) are parties to a child support case registered with Services Australia - Child Support (Child Support) in relation to financial support to be provided for their daughter (born 2008) (the child). The application concerns a single decision of Child Support about the percentage of care determinations for each parent for the child utilised in calculation of the child support liability.
2. The existing percentage of care determinations applying in the child support case for the child were 0% to the Father and 100% to the Mother from 17 September 2020.
3. On 4 March 2022[1], the Father notified Child Support that the care of the child had changed to 58% to the Father (8 nights per fortnight) and 42% to the Mother (6 nights per fortnight) from 25 December 2021.
4. On 6 May 2022, Child Support decided to revoke the existing percentage of care determinations and record new percentage of care determinations of 51% to the Father and 49% to the Mother from 4 March 2022. In making that decision, Child Support recorded that the Father's position was that the change in care occurred on 4 February 2022, however, the Mother's position was that the change occurred on 14 March 2022, with Child Support electing to utilise the date of notification, 4 March 2022, as the date of change in care given the dispute. Further, it was noted that the Father had accepted that the care percentage of the child was 50% to each parent.
5. Child Support also decided on 6 May 2022 to record further new percentage of care determinations of 100% to the Father and 0% to the Mother for the child from 4 April 2022, a decision which was subsequently changed on objection on 13 July 2022 to percentage of care determinations of 79% to the Father and 21% to the Mother, as affirmed by the AAT on review on 26 June 2023. Notably, this subsequent decision is not the subject of this application to the Tribunal.
6. On 7 December 2022, the Father objected to the 6 May 2022 decision in relation to the 4 March 2022 advised change in care of the child stating that he had 58% care from 4 February 2022. On 11 December 2023, a Child Support objections officer disallowed the objection.
7. On 25 March 2024, following the application on 12 December 2023 by the Father for first review of that decision, the Social Security and Child Support Division of the Administrative Appeals Tribunal (the AAT) affirmed the 11 December 2023 objection decision.
8. On 2 April 2024, the Father lodged an application with the AAT seeking second review of the decision.
9. On 14 October 2024, the AAT became the Administrative Review Tribunal (the Tribunal). Under the transitional provisions in the Administrative Review Tribunal (Consequential and Transitional Provisions No. 1) Act 2024, proceedings in the AAT that were not finalised before 14 October 2024 are taken to be continued and finalised by the Tribunal. Anything done in relation to the proceeding before 14 October 2024 is taken to have been done by the Tribunal.
10. The Father, the Respondent's representative and the Mother participated by telephone in a hearing before me on 5 June 2025, with the Father and the Mother giving sworn evidence.
11. In addition to the Father's and the Mother's oral evidence and the oral submissions at hearing from all parties, I took into account the following documents before me:

(a) Calendar for March 2022 provided by the Father, marked as Exhibit A1;

(b) Calendar for April 2022 provided by the Father, marked as Exhibit A2;

(c) Documents provided by the Respondent pursuant to section 37 of the then Administrative Appeals Tribunal Act 1975 (the AAT Act), pages numbered 1 to 470, marked as Exhibit R1;

(d) Documents provided by the Respondent pursuant to section 25 of the Administrative Review Tribunal Act 2024, documents S1 to S7, pages numbered 2 to 19, marked as Exhibit R2;

(e) Documents provided by the Respondent pursuant to section 25 of the Administrative Review Tribunal Act 2024, documents S8 to S10 pages numbered 2 to 17, marked as Exhibit R3; and

(f) the Respondent's Statement of Facts, Issues and Contentions (SFIC) dated 5 May 2025.

1. The statutory provisions relevant to this review are contained in the Child Support (Assessment) Act 1989 (the Act) and the Child Support (Registration and Collection) Act 1988 (the Registration and Collection Act). Unless otherwise noted, all legislative references in these Reasons are to the Act. The legislation provides the Registrar, that is, Child Support, and the Tribunal on review, with rules for assessing and changing percentage of care determinations, which are then used as part of the child support formula to assess child support rates.
2. I also had regard to the Child Support Guide (the Guide) where relevant. As recognised by the Federal Court in MDXJ v Secretary, Department of Social Services [2020] FCA 1767:

The part which a governmental policy should ordinarily play in the determinations of the Tribunal is a matter for the Tribunal to determine, in the context of the particular case, informed by considerations of the desirability of consistency of administrative decisions, but balanced against the ideal of justice in the individual case (Hneidi v Minster for Immigration and Citizenship [2010] FCAFC 20: (2010) 182 FCR 115 at [43]). Further, it is well-established that the Tribunal must make the correct or preferable decision in each case on the material before it and that the Tribunal is at liberty to adopt whatever policy it chooses, or no policy at all, in fulfilling its statutory function (Re Drake and Minister for Immigration and Ethnic Affairs (No 2) (1979) 2 ALD 634 at 642-643 per Brennan J). The important matter is compliance with the terms of the relevant statute itself Minster for Home Affairs v G [2019] FCAFC 79; (2019) 266 FCR 569.

1. I acknowledge that in the absence of any statutory indication to the contrary, any lawful executive policy enacted to guide the exercise of a statutory power is a relevant factor for me to take into account in performing the review task and that a lawful approach allows the adoption of appropriate policy as a guide but not so as to control the making of the decision.
2. The child support legislation provides for assessment of child support using a formula taking into account numerous variables, including relevant care percentages for each party to a child support assessment.
3. Sections 49 and 50 require initial percentage of care determinations to be made upon initial registration of a child support case, usually based upon the actual care of a child parties to a child support case have. Existing percentage of care determinations are usually required to be revoked, pursuant to either section 54G, 54F or 54H, when a change of care occurs and new percentages of care apply.
4. Except for in certain circumstances not relevant to this case, care percentages are to be determined corresponding to the actual care a person has had, or is likely to have, during a care period.
5. As to the appropriate care period to be considered, a care period is defined in the Act as being such a period as considered to be appropriate having regard to all the circumstances. The Guide provides that a care period is generally the 12-month period starting from the date the actual care of the child began or changed. The same care arrangements will then be assumed to continue to apply after the end of the care period unless Child Support is notified or becomes aware of a subsequent change in the pattern of care and the requirements of the legislation are satisfied for a new care decision to be made.
6. Both sections 49 and 50 first require consideration of whether the relevant person has had, or is likely to have, no pattern of care or a pattern of care for a child for the care period. If applicable, section 49 then requires a percentage of care determination of 0% for a person with no pattern of care. If applicable, section 50 then requires that the percentage of care determined for the relevant person must be a percentage that corresponds with the actual care the person has had, or is likely to have, during the care period. Section 54A provides that the actual care of a child that a person has had, or is likely to have, during a care period, may be worked out based on the number of nights that a child was, or is likely to be, in the care of a person.
7. The legislative test therefore first requires consideration of whether a person has had, or is likely to have, a pattern of care of a child for a care period and, if so, then assessment of the actual care a person has had, or is likely to have, during the care period is required.
8. As was recognised by Thomas J in the Federal Court case of Child Support Registrar v BKCZ [2023] FCA 1109 at [72], section 50 allows a decision-maker flexibility to consider what care a person 'had or is likely to have' depending upon when, relative to the care period, the decision is being made.
9. The issues which arise in this case are:

(a) Are the existing percentage of care determinations of 0% for the Father and 100% for the Mother, in relation to the 4 March 2022 notification of a change in care, to be revoked? and, if so,

(b) What are the new percentage of care determinations for the Father and the Mother?

(c) What are the dates of application of the new percentage of care determinations? And

(d) What is the date of effect of the Tribunal's decision?

1. The documents in evidence show that varying dates have been advised from time to time as to from when the relevant change in care of the child occurred. As already noted, on 4 March 2022, the Father notified Child Support that the care of child had changed to 58% to the Father (8 nights per fortnight) and 42% to the Mother (6 nights per fortnight) from 25 December 2021. Other documents show the following advised dates from which the change in care occurred:

(a) on 8 April 2022[2], the Mother advised Child Support that the Father did have care of the child (and their other children not the subject of this application) from 11 January 2022 and the children returned to her care on 25 January 2022, that from 4 February 2022, the Father commenced care of 3 nights per fortnight and that the child did start to stay with the Father for 7 nights (per fortnight) from sometime in March;

(b) on 8 April 2022[3], the Father confirmed that he did look after the children (including the child) from 11 January 2022 until 25 January 2022 and that he had care of the child for 8 nights per fortnight from a date he would later confirm and he is not sure why he previously advised the care as from 25 December 2021;

(c) on 6 May 2022,[4] the Father advised that he had provided 8 nights care per fortnight of the child from 4 February 2022;

(d) On 27 July 2023, 4 October 2023,[5] the Father advised that the date of change in care of the child was 14 January 2022; and

(e) On 25 March 2024, the Father is recorded as advising the Tribunal on first review that he had care of the child every second week from 28 January 2022.

1. The Father's position is that Christmas Day 2021 was the first time he had custody back of the child in person. The child then started being at his house, staying for a bit over a week from 11 January 2022, returning to the Mother's for the week prior to school starting. Then after the first week of school, the child started staying with him every second week plus every other second Thursday night. Once this pattern had continued for four weeks, a consistent pattern, he contacted Child Support to advise of the change. He needed to wait for this period to ensure that the child's words, as to where she would be staying, were matched by her actions. He was later advised by someone at Child Support to go back to the first day that he had care of the child, in January when advising of the change in care. It was also suggested to him by someone at Child Support that he should compromise, in relation to the care to be recorded, as 50/50 from 4 March 2022.
2. As discussed with the Father and Mother at hearing, text messages between in evidence,[6] suggest that the child was in the Father's care for the nights of 11 to 16 January 2022 inclusive so as to avoid exposure to COVID-19 at the Mother's house the time.
3. The Father referred to calendars provided for the months of January, February, March and April 2022 in relation to the care of the child advising that the calendars had been kept by the child at the time and were calendars that she started keeping from 4 March 2022 at his request as to where she was staying, with the calendars for January and February 2022 therefore being filled out retrospectively.
4. At hearing, I went through the nights of care of the child that the Father had between 11 January 2022 to 3 April 2022 with both the Father and the Mother. In summary, the Father's position, by reference to text messages between the Father and the Mother, and the calendars, was that he commenced caring for the child every second week, plus the Thursday night in the other week, not from 4 February 2022 but from 1 February 2022 until 4 April 2022 when the care again changed. The Mother's position was that she does not have access to the calendars that she kept of the care occurring at the time to provide to the Tribunal, however, her diary based on those calendars do not show the Father having any care of the child until the weekend prior to 21 February 2022 with the child (and the other two children) coming back into her care on that date after that weekend with the Father.
5. A text message from the Father to the Mother on Friday 4 February 2022[7] refers to the Father hoping to pick up all three children from school that day and to spend the weekend with them with it noted that the Father missed them very much. At hearing, the Father said that the child had already been in his care from 1 February 2022, with the reference to missing them being to the other two children. The Father also relied upon the child's calendar as showing her in the Father's care from 1 February 2022.
6. Of further note is a text message from the Mother to the Father on 10 February 2022 which includes a statement to the effect that the new care the Father was exercising of the child shouldn't be considered 'an ongoing arrangement yet because we've just started trying to get into a steady routine with school going back'.[8]
7. I am satisfied that although the Father had care of the child from 11 January 2022 to 25 January 2022, there was no change in the pattern of care of the child occurring at that time and that, rather, this was one off care provided by the Father necessitated by COVID-19.
8. The Mother had no record of the Father having care of the child at all in February 2022 prior to 21 February 2022. I acknowledge the Father's evidence at hearing that the care change occurred on 1 February 2022. Notably however the Father from time to time has given varying dates as to when the care changed, as noted in paragraph 23 of these Reasons. Given the uncertainty arising based upon the Father's recounting of the date from time to time, I consider the best evidence of the date the care changed is the contemporaneous text messages between the parents. I am satisfied based upon the text messages at the time in evidence that the Father had care of the child from at least 4 February 2022 and that from that time the Father commenced a pattern of care of the child every second week. In reaching this conclusion I have taken into account the Mother's 10 February 2022 text message and her view that the change in care shouldn't be considered an ongoing arrangement yet. Nonetheless, I am satisfied based on the care the Father had exercised of the child to that point and the care exercised subsequently that a change in care occurred from 4 February 2022.
9. As regards the additional further night of care every other Thursday night in the other week contended by the Father, the Mother did not disagree that that additional care may have occurred on occasion but said that the arrangement she had with the child was that that additional care would then be made up (to the Mother) at a subsequent date however she was unable to point to when that made-up care occurred. I discussed with the Father and Mother at hearing that text messages on Sunday 6 February 2022,[9] Thursday 10 February 2022[10] and Tuesday 22 February 2022[11] are suggestive that whilst the Father may have taken the child to PT sessions on the respective Thursdays in those weeks, the child returned to the Mother's care on those nights. The Father's evidence was that despite what those text messages suggest, he did have overnight care of the child on those Thursday nights (10 February 2022 and 24 February 2022) and what was suggested in the text messages (the child staying at the Mother's those nights) did not occur. No other text messages directly address the additional Thursday nights. I acknowledge the Father's evidence that his recollection is that he had the additional Thursday nights of care in the relevant period and that his agreement to 50/50 care for the purposes of the 6 May 2022 decision was only a compromise. However, absent corroboratory evidence of the additional Thursday night care and given the text messages suggest to the contrary, I am not satisfied that the Father had care every other Thursday night additional to the week about care. Alternatively, to the extent that he may have had care on those Thursday nights, which was not made up, I am satisfied that that care was a minor variation to the care not constituting a change to the pattern of care that was otherwise occurring. (Section 4.1.3 of the Guide).
10. As discussed with the parties at hearing, I have placed minimal if any weight on statements of any third parties. I prefer the text messages between the parties as the best contemporaneous evidence of what care was occurring, to some extent the care calendars in evidence and the oral evidence at hearing having regard to those documents.
11. Having had regard to all of the evidence, I am satisfied that there was a change in the pattern of care of the child from 4 February 2022 with that pattern of care continuing, with minor variations, until 3 April 2022. The appropriate care period is therefore 4 February 2022 to 3 April 2022. I am further satisfied that the pattern of care in the care period was week about care of the child between the Father and the Mother, with minor variations. The actual care as recorded in the child's calendar in March 2022 varies from that pattern to some extent. For example, the March 2022 calendar notes that the child stayed with the Father for longer than a week on that occasion (with COVID-19 noted on the calendar on 6 March 2022 and confirmed at hearing as being the reason for the change). Further, the calendar records, as confirmed by the Father in evidence, that the child's visit in one of the weeks she was staying with the Father was cut short at the child's request to spend the weekend with her maternal grandfather. To the extent that these were variations to the pattern of care, I consider these, together with any care every second Thursday night by the Father, to be minor departures from the then pattern of care consistent with minor variations of this nature recognised in the Guide that can occur from time to time without constituting a change to the pattern of care. (Section 4.1.3 of the Guide).

Issue 1: Are the existing percentage of care determinations of 0% for the Father and 100% for the Mother, in relation to the 4 March 2022 notification of a change in care, to be revoked?

1. I have found that the care of the child changed from 4 February 2022 to care corresponding to 50% to the Father and 50% to the Mother.
2. Section 54F provides that an existing care percentage decision must be revoked if the Child Support Registrar is notified, or becomes aware, that the actual care that is taking place does not correspond with the existing percentages of care recorded, that the change would alter the cost percentage used for a parent in the administrative assessment, and that section 54G does not apply and section 51 does not apply or no longer applies.
3. Section 55C contains a table that is used to work out a person's cost percentage:

1. Section 54G provides that a care determination must be revoked if a parent was to have at least regular care pursuant to an existing percentage of care determination and the other parent was to have more than 0% care, they have no care or less than regular care (subsection 5(2) defines regular care as being care between 14% and 35%) despite the other responsible person making care available, and the change in care was notified within a reasonable period of time. The Father was not previously having at least regular care. Section 54G therefore does not apply. Section 51 also has no application in the circumstances of this matter.
2. Care of 50% to the Father and 50% to the Mother does not correspond with the existing percentage of care determinations recorded by Child Support of 0% to the Father and 100% to the Mother. A change in care to 50% to the Father and 50% to the Mother would change each parent's cost percentage pursuant to the table in section 55C.
3. The existing percentages of care of 0% to the Father and 100% to the Mother are therefore required to be revoked pursuant to section 54F.

Issue 2: What are the new percentage of care determinations for the Father and the Mother?

1. Percentage of care determinations are required pursuant to section 50. I determine that the Father's percentage of care is 50% and the Mother's percentage of care is 50%.

Issue 3: What is the date of application of the revocation of the pre‑existing percentage of care determinations and the date of application of the new percentage of care determinations?

1. Pursuant to paragraph 54F(3)(a), as the change in care was notified by the Father on 4 March 2022 within 28 days after when I have found the change occurred on 4 February 2022, revocation of the existing percentages of care for both parents takes effect the day before the date I have found the care changed, that is, on 3 February 2022.
2. Pursuant to section 54B, new percentage of care determinations apply from the application day, that is, the day immediately after revocation of the previous percentage of care determinations. Therefore, the new percentage of care determinations of 50% for the Father and 50% to the Mother apply from 4 February 2022.

Issue 4: What is the date of effect of the Tribunal's decision?

1. If an objection is made more than 28 days after the notice of the original decision was served upon a person, and the decision following the objection is to vary or substitute the decision, the new decision only takes effect from the day the objection was lodged unless there are special circumstances that prevented the objection from being made within that 28-day period: subsections 87AA(1) and (2) of the Registration and Collection Act.
2. Child Support's decision was made on 6 May 2022 and sent to the Father by post on that date.
3. Although the Father's objection has previously been recorded by the Respondent as having been lodged on 27 July 2023, the Respondent in written and oral submissions submitted and accepted that the Father had first objected on 7 December 2022.[12] It was recognised that there were multiple care decisions being actioned, in relation to multiple children of the Father and the Mother, at around the same time. Call logs provided in supplementary documents provided by the Respondent (Exhibit R2) show that the Father contacted Child Support on numerous occasions between 19 May 2022 and 7 November 2022. At hearing, the Father's evidence included that he originally compromised on 50/50 care being recorded from 4 March 2022 including on the basis that 100% care was recorded for him from 4 April 2022. However, the 4 April 2022 care was subsequently changed to 79% care to him and was then subject of a different review to the AAT which wasn't finalised until 26 June 2023. He said it was very complicated because there were a number of decisions being made at around the same time and they were crossing over and objections and objection decisions were going back and forth and he was at times told wrong information about what was happening. He submitted there were special circumstances preventing him from lodging an objection to 7 December 2022 on that basis. The Mother acknowledged at hearing that it was fair to say that there were a number of decisions and contacts occurring at around the same time and that it was understandable that confusion could arise.
4. I am satisfied in the particular circumstances of this matter, that there were special circumstances such that the Father was prevented from lodging an objection within 28 days of being given the objection decision, in particular because of the confusion arising because of the multiple care and objection decisions taking place at around the same time. I find that the reference to 28 days in paragraph 87AA(1)(b) of the Act is therefore a reference to a longer period such that the Father's objection on 7 December 2022 was made within the required period such that there is no limitation on the otherwise date of effect of the Tribunal's decision.

The Tribunal sets aside the decision under review and substitutes a new decision that, in respect of the child:

1. the existing percentage of care determination of 0% to the Father is revoked from 3 February 2022 and replaced with a new percentage of care determination of 50% applying from 4 February 2022; and

1. the existing percentage of care determination of 100% to the Mother is revoked from 3 February 2022 and replaced with a new percentage of care determination of 50% applying from 4 February 2022.

The Tribunal determines pursuant to section 87AA of the Child Support (Registration and Collection) Act 1988 that section 87AA applies as if the reference to 28 days in paragraph 87AA(1)(b) was a reference to a longer period extending until 7 December 2022.

[5] Pages 348 and 350 of Exhibit R2 and to the Tribunal on first review.