RHKX and Child Support Registrar (Child support second review)

[2025] ARTA 1414

RHKX and Child Support Registrar (Child support second review) [2025] ARTA 1414 (14 August 2025)

Applicant:RHKX

Respondent:  Child Support Registrar

Other Party:  WNBX

Tribunal Number:                2024/9600

Tribunal:Senior Member S Trotter (second review)

Place:Brisbane

Date:14 August 2025

Decision:The Tribunal sets aside the decision under review and in substitution decide that the existing percentage of care determinations of 68% to the Father and 32% to the Mother are not revoked.

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.

Catchwords

CHILD SUPPORT – care percentage determination – whether pre-existing percentages of care determinations are to be revoked – consideration of section 54F, 54G and 54H of the Child Support (Assessment) Act 1989 – appropriate care period – whether change in cost percentage – pre-existing percentage of care determinations not revoked

Legislation

Administrative Appeals Tribunal Act 1975 (Cth)
Administrative Review Tribunal Act 2024 (Cth)
Administrative Review Tribunal (Consequential and Transitional Provisions No. 1) Act 2024
(Cth)

Child Support (Assessment) Act 1989 (Cth)

Cases

Child Support Registrar v BKCZ [2023] FCA 1109
MDXJ v Secretary, Department of Social Services [2020] FCA 1767

Secondary Materials

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

Statement of Reasons

1. Mr RHKX (the Father) and Ms WNBX (the Mother) are parties to a child support case registered with Services Australia – Child Support concerning financial support for their daughter, born April 2008 (the child). The Respondent is the Child Support Registrar, the statutory officeholder responsible for administering the scheme within Services Australia and will be referred to as Child Support in these Reasons. This application concerns a single Child Support decision about the percentage of care determinations for each parent for the child used in calculating the child support liability.

2. The existing percentage of care determinations for the child were 68% to the Father and 32% to the Mother from 7 August 2021. Child Support records show that, on 2 October 2023, the Mother notified Child Support that care had changed to 64% for the Father and 36% for the Mother from 10 August 2023.

3. On 28 March 2024, Child Support revoked the existing percentage of care determinations and recorded new percentage of care determinations of 64% to the Father and 36% to the Mother from 10 August 2023. Notification of the change was given more than 28 days after the care change, and although the recorded decrease, from 68% to 64%, for the Father was applied from 10 August 2023 (the date of the care change), the recorded increase, from 32% to 36%, for the Mother applied from 2 October 2023 (the date of notification).

4. On 16 April 2024, the Father objected to the 28 March 2024 decision. On 27 August 2024, a Child Support objection officer partly allowed the objection, revoking the earlier determinations and determining new percentages of care of 65% for the Father applying from 10 August 2023 and 35% for the Mother applying from 2 October 2023.

5. On 31 October 2024, following the Father’s 28 August 2024 application for first review, the Social Security and Child Support Division of the Administrative Appeals Tribunal (the AAT) varied the objection decision, finding that the earlier percentage of care determinations were to be revoked, with new percentage of care determinations of 64% for the Father applying from 10 August 2023 and 36% for the Mother applying from 2 October 2023.

6. On 19 November 2024, the Father lodged an application with the AAT seeking second review of the decision.

7. The Father, the Father’s representative, the Respondent’s representative and the Mother participated in a telephone hearing before me on 23 June 2025. The Father and the Mother gave sworn evidence.

8. 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, marked either as exhibits or for identification as follows:

   (a) Documents provided by the Respondent on first review pursuant to section 37 of the then Administrative Appeals Tribunal Act 1975 (the AAT Act), pages numbered 1 to 226, marked as Exhibit 1;

   (b)  Documents provided by the Father on first review, pages numbers A1 to A37, marked as Exhibit 2;

   (c) Documents provided by the Respondent pursuant to section 25 of the Administrative Review Tribunal Act 2024, documents S1 to S9, pages numbered 1 to 34, marked as Exhibit 3;

   (d)  Submissions from the Father dated 3 February 2025 and appendices, marked for identification as Exhibit 4;

   (e)  Statement of Facts, Issues and Contentions of the Father dated 21 March 2024 (sic 21 March 2025), marked for identification as Exhibit 5;

   (f)    Statement of Facts, Issues and Contentions of the Father dated 17 April 2025, marked for identification as Exhibit 6; and

   (g)  Second Review Additional Submission from Applicant in response to Registrar’s Statement of Facts, marked for identification as Exhibit 7;

   ISSUES

9. The relevant statutory provisions are contained in the Child Support (Assessment) Act 1989 (the Act). Unless otherwise noted, legislative references are to the Act. The legislation gives the Registrar, that is, Child Support and the Tribunal on review, rules for assessing and changing percentage of care determinations, which are then used in the child support formula to assess child support rates.

10. I have also considered 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.

11. I acknowledge that, absent statutory indication to the contrary, lawful executive policy guiding the exercise of a statutory power is a relevant factor for me to take into account in performing the review task, provided it is used as a guide and not to control the decision.

12. The child support legislation provides for assessment of child support using a formula that takes into account various factors, including each parent’s percentage of care.

13. Sections 49 and 50 require initial percentage of care determinations when a case is registered, usually based on the actual care at the time. Existing determinations are usually revoked, pursuant to either section 54F, 54G or 54H, when a change of care occurs and new percentages apply.

14. Except in limited circumstances not relevant here, care percentages are determined corresponding to the actual care a person has had, or is likely to have, during a care period.

15. A “care period” is defined in the Guide as a period considered appropriate in all the circumstances. The Guide states that a care period is generally the 12-month period from the date the actual care of the child began or changed. The same arrangements are assumed to continue unless Child Support is notified of, or becomes aware of, a subsequent change meeting the legislative requirements for revocation.

16. Sections 49 and 50 first require determining whether a person has had, or is likely to have, a pattern of care. If not, or if the care is less than “regular care” (defined as 14-35%), section 49 requires a percentage of care determination of 0%. If applicable, section 50 requires that the percentage of care determined correspond with the actual or likely care 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.

17. As was recognised by Thomas J in the Federal Court case of Child Support Registrar v BKCZ [2023] FCA 1109 (BKCZ) at [72], section 50 allows a decision-maker flexibility to consider what care a person ‘had or is likely to have’ depending upon when the decision is made, and the evidence then available, in relation to the care period.

18. The issues for determination are:

    (a)  Are the pre-existing percentage of care determinations of 68% for the Father and 32% for the Mother, in relation to the 2 October 2023 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? and

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

    CONSIDERATION

19. The Father’s position is that a court order of 28 June 2023 provided for the Mother’s care to increase from overnight care every Friday, Saturday and Sunday every second week during school term, plus 50% of school holidays to include additionally every alternating Thursday night. The order also specified that the school holidays were to be gazetted school holidays. On this basis, care was to change to 33% for the Mother (increased from 32%) and 67% for the Father (decreased from 68%). The Father’s position is that care occurred pursuant to the 28 June 2023 court order from 10 August 2023 until 1 November 2023 when, in breach of court orders, the child remained in the Mother’s care until the afternoon of 19 December 2023. From 19 December 2023, care again followed the court order until 25 November 2024, when the court orders were again not followed from 25 to 27 November 2024 and from 9 to 11 December 2024.

20. The Father gave evidence that he took reasonable action regarding the breach of the court order from 1 November 2023 to 19 December 2023, including contacting the Mother requesting the child’s return, sending solicitor’s letters and applying to the court. On 16 May 2024[1] the court found that the Mother had breached the orders from 1 November 2023 to 19 December 2023 without reasonable excuse.

    [1] Exhibit 4, Appendix A.

21. The Father submitted that the relevant care period for the Mother’s 2 October 2023 notification is 28 June 2023 to 31 October 2023. During that period, care was in accordance with the 28 June 2023 order, corresponding to 33% care for the Mother and 67% for the Father. He argued that because the change in care from 32% to 33% for the Mother and from 67% to 68% for him, did not affect either parent’s cost percentage, section 54F does not permit revocation.

22. As regards the period 1 November 2023 to 18 December 2023, the Father submitted that the pre-existing determinations should continue to apply. He submitted that revocation would be required pursuant to section 54G and that section 51 would apply to continue the pre-existing determinations for an interim period. Actual care then reverted to the court ordered care, which would not have required a change from the existing percentages. I canvassed with the parties whether the 1 November 2023 change in care, which was not disputed, had been notified to the Respondent. I noted that the Mother’s 2 October 2023 notification could not be linked to a subsequent change in care. It was identified that on 20 November 2023 there was a contact between the Father and a representative of the Respondent with a record of that contact appearing at pages 55 and 56 of Exhibit 1. That contact was ostensibly for the purpose of ascertaining the Father’s position regarding the change in care notified by the Mother on 2 October 2023. However, as recorded on page 56 of Exhibit 1, the Father also stated during that contact that from 1 November 2023 the Mother had had care of the child. Further, the Respondent’s records, at page 83 of Exhibit 1, show that on 22 December 2023 the Mother contacted and provide a further update on care arrangements, confirming that the Father had not had care of the child from 1 November 2023 to 20 December 2023, after which court ordered care then resumed.

23. The Mother’s evidence was that except for one missed Thursday night (made up the following week), care occurred in accordance with the 28 June 2023 order from 10 August 2023 until November 2024, except for the period 1 November 2023 to 18 December 2023 when she retained care as decided by the then 15-year-old child. The Mother stated that she did not have a position overall in relation to the Tribunal’s decision on second review, but that the current decision on first review of 36% to her and 64% to the Father “sounded about right”.

24. I am satisfied that there was a change in the care from 10 August 2023, with the Mother’s care increasing to every alternate Thursday nights in addition to the existing three nights of care per fortnight, plus half the school holidays. Whether this change requires revocation of the pre-existing percentage of care determinations as at the date of the Mother’s notification on 2 October 2023 and application of new percentages of care is a matter to be determined by reference to the relevant legislation.

    Issue 1: Are the pre-existing percentage of care determinations of 68% for the Father and 32% for the Mother, in relation to the 2 October 2023 notification of a change in care, to be revoked?

25. As already noted, the provisions potentially relevant to revocation are sections 54F, 54G and 54H. Section 54F only applies if section 54G does,[2] so it appropriate to first consider section 54G.

    Revocation pursuant to section 54G

    [2] Subparagraph 54F(1)(c)

26. Section 54G provides that a care percentage determination must be revoked if a parent with at least regular care under an existing determination, and where the other parent has more than 0% care, has no care or less than regular care despite the other person making care available, and the change is notified within a reasonable time. The change that occurred on 10 August 2023 did not result in either parent having less than regular care. Section 54G therefore does not apply.

    Revocation pursuant to section 54F

27. If the criteria in paragraphs 54F(1)(a) to (d) are met, a pre-existing percentage of care determination must be revoked pursuant to section 54F.

28. Paragraph 54F(1)(a) requires revocation where the Child Support Registrar is notified, or becomes aware, that the actual care differs from recorded percentages.

29. I have found that the care on 10 August 2023 to care corresponding to 67% for the Father and 33% for the Mother, compared to recorded percentages of 68%/ 32%. The actual care therefore did not correspond with the recorded percentages. The criterion in paragraph 54F(1)(a) is met.

30. Paragraph 54F(1)(b) is met if the change would alter a parent’s cost percentage.

31. In general, the percentage of care reflects actual care and links to cost percentages in section 55C, which sets out the care ranges and corresponding cost percentages as follows:

Cost percentages
Item	Column 1 Percentage of care	Column 2 Cost percentage
1	0 to less than 14%	Nil
2	14% to less than 35%	24%
3	35% to less than 48%	25% plus 2% for each percentage point over 35%
4	48% to 52%	50%
5	more than 52% to 65%	51% plus 2% for each percentage point over 53%
6	more than 65% to 86%	76%
7	more than 86% to 100%	100%

1. The percentage of care corresponding to the actual care occurring depends upon the care period utilised. The term “care period” is not defined beyond sections 49 and 50, which provide it is a period considered appropriate having regard to all of the circumstances.

2. As already noted, the Guide states that a care period is generally 12-month period starting from the date the actual care began or changed. However, the Guide also recognises that a shorter or longer care period may be more appropriate.

3. The Father submitted that the appropriate care period was from when the care changed on 10 August 2023 up until the day before it changed again on 1 November 2023. It is not disputed that the Mother then retained care of the child from 1 November 2023 until the afternoon of 19 December 2023. The Respondent’s oral submissions were that it was open to the Tribunal to find such a care period. As already noted, the Mother did not adopt a position in relation to the matter and made no specific submissions.

4. I am satisfied that it is appropriate that a care period extend from the time care changes until such time care subsequently changes again. This is consistent with the next care period starting when the actual care changed, an approach consistent with the Guide. For similar reasons as recognised in BKCZ, I can consider what is appropriate in the circumstances based upon all of the evidence now before relating back to that time. Given the undisputed further change in care on 1 November 2023, I am satisfied in the circumstances that the appropriate care period is 10 August 2023 to 31 October 2023.

5. Based on the undisputed evidence at hearing, I find that the care occurring in the care period 10 August 2023 to 31 October 2023 was pursuant to the 28 June 2023 court order, corresponding to 33% for the Mother and 67% for the Father.

6. As seen in section 55C, a change from 68% to 67% for the Father and from 32% to 33% for the Mother does not alter either parent’s cost percentage (remaining at 76% for the Father and 24% for the Mother). It follows that section 54F does not permit revocation.

   Revocation pursuant to section 54H

7. Section 54H provides that an existing percentage of care determination may be revoked even if the cost percentage for a parent would not change. The Guide, at Topic 4.1.5, recognises that this is discretionary and may be used to ensure accurate records. However, given the very minor change which results in no change to the parents’ respective cost percentages, and therefore no change to the child support assessment, I do not consider discretion should be exercised.

   Conclusion

8. I determine that revocation does not apply under sections 54F,54G or 54H in relation to the 10 August 2023 change notified by the Mother on 2 October 2023. The pre-existing percentage of care determinations for the Father and the Mother are therefore not revoked and the decision under review will be set aside with a substituted decision to that effect.

9. Given my conclusion on Issue 1, it is unnecessary to consider Issues 2 and 3.

   ADDITIONAL OBSERVATIONAL

10. Other background matters of understandable importance to both parents were raised, either in written submissions during the hearing, but are not relevant the Tribunal’s determination, including as addressed in the following paragraphs.

    Changes in care on 1 November 2023 and 19 December 2023

11. It was not in dispute that care changed on 1 November 2023 (when the Mother commenced 100% care of the child until 18 December 2023) and again on 19 December 2023, or thereabouts (when the court ordered care of the child resumed).

12. As noted earlier, both of these changes were notified to the Respondent but were not actioned as new care events requiring consideration of whether existing care percentage determinations should be revoked and replaced. The Respondent instead only actioned the earlier change in care notified on 2 October 2023. It was open for the Respondent to action all changes and make any required determinations but it did not do so.

1. The Father submitted that the 1 November 2023 change, notified on 20 November 2023, should have resulted in the application of an interim period under section 51 because that change would have resulted in revocation under section 54G and, further, the requirements of section 51 were met. Any such consideration is not before the Tribunal in relation to this application. However, the Father contended that section 51 would apply because he took reasonable action to have the court ordered care occur and, further that revocation under section 54G would apply. He based this on the evidence that, from 1 November 2023, he did not have regular care because of the child’s actions (rather than because of the Mother withholding care) and that this situation - recognised by the Guide at Topic 4.1.7 - would permit revocation pursuant to section 54G in the circumstances and the operation of an interim period pursuant to section 51.

2. These matters are noted by way of observation only and are not for determination in this application. The pre-existing percentage of care determinations of 68% to the Father and 32% to the Mother, which I have found are not to be revoked in relation to the 2 October 2023 notification, will continue to apply unless and until a subsequent decision that there was a change in care requiring revocation of those percentages.

   Subsequent changes in care including, if relevant, in November 2024 and December 2024

3. As discussed, the legislative scheme provides that when Child Support is notified, or otherwise becomes aware, of a change in care, it must determine whether existing determinations are to be revoked and replaced with new percentage of care determinations. Any such further decision is separate from this review and carries with it it’s own review rights.

4. It is for either parent to follow up with Child Support about subsequent changes if they wish. Until such a change is accepted as requiring revocation of the existing percentages of care, the pre-existing percentage of care determinations of 68% for the Father and 32% for the Mother will continue to apply.

   Other matters

5. I also observe the following further matters raised during the course of this review, which are not relevant to the issues before or within the jurisdiction of the Tribunal. These included, but were not limited to:

   (a)  The Tribunal has no power to award costs. Mr Singh indicated that the Father would not pursue costs.

   (b)  The Tribunal has no power to enforce court orders or to make orders about future care.

   (c)   While this decision, and related decisions, may impact the resulting child support liability for relevant periods, the Tribunal has no role to play in the calculating amounts payable or ordering the payment or repayment of any child support.

   DECISION

   The Tribunal sets aside the decision under review and substitutes a new decision that the existing percentage of care determinations of 68% to the Father and 32% to the Mother are not revoked.

Date of hearing:	23 June 2025
Solicitors for the Applicant:	Mr S Singh, DBL Lawyers
Solicitors for the Respondent:	Ms M Kopic, Services Australia
Other Party:	Self-represented