Adjusted Taxable Income (ATI) for Mr Tierney was set at $300,000. There was no objection to this decision.

On 20 March 2023, we made a COA decision, which was objected to, then appealed through the

AAT. Therefore, the decision in place is the AAT decision made on 24 January 2024.

The Tribunal sets aside the decision under review and in substitution the Tribunal decides as

Mr Tierney s adjusted taxable income for the 2020/21 financial year is varied to

Mr Tierney s adjusted taxable income for the 2021/22 financial year is varied to

Mr Tierney s adjusted taxable income for the 2022/23 financial year is varied to

For the period from 16 November 2022 to 15 November 2023, Mr Tierney s annual rate of child

On 19 September 2024, we made a COA decision. For the period 1 July 2024 to 18 September

On 21 February 2024, we applied the 24 January 2024 AAT decision to the assessment as follows:

- 01/01/2022 to 31/03/2023 Mr Tierney s 2020/21 ATI was set to $588,824.

- 01/04/2023 to 30/06/2024 Mr Tierney s 2021/22 ATI was set to $369,236.

On 20 August 2024, whilst managing your new COA application (lodged 13 June 2024), we

identified that our application of the 24 January 2024 AAT decision was incorrect.

Although the AAT summary decision did not include the specific dates of effect of their decision,

they noted in paragraph 90 that the period of effect for adjustments was 16 November 2022 to 30

June 2024. We had in error applied Mr Tierney s incomes for a period outside these dates, and this

The error correction resulted in Mr Tierney s income now reflecting as:

- 01/01/2022 to 31/05/2022 ATI is $300,000 (as per COA decision 21/07/2021)

- 01/06/2022 to 10/08/2022 2020/21 Australian Taxation Office income of $288,894.

- 11/08/2022 to 15/11/2022 2022/23 estimate of income $206,579.

- 16/11/2022 to 31/03/2023 2020/21 ATI set to $588,824 (AAT decision 24/01/2024)

- 01/04/2023 to 30/11/2023 2021/22 ATI set to $369,236 (AAT decision 24/01/2024)

- 01/12/2023 to 30/06/2024 2022/23 ATI set to $550,000 (AAT decision 24/01/2024)

Our review of the decisions confirmed this error correction was appropriate, and all relevant

The error correction reduced the amount we assessed Mr Tierney to pay you for past periods,

resulting in an overpayment. We acknowledge your advice that not receiving payments whilst this

overpayment offsets against the ongoing amounts we are assessing him to pay you, is causing

Where you believe the error correction decision was legally or technically incorrect you have

We will inform you of the outcome of the objection s decision. You can lodge an appeal with the

Administrative Review Tribunal (ART) if you disagree with the objection s decision, they have the authority to review most of Service Australia s decisions.

1. On 16 April 2025, an objections officer disallowed Ms Sheehan's objection:

The Registrar has the power to amend an assessment or vary the Child Support Register to correct

any error or mistake, whether or not made by the Registrar.

There are limited circumstances where an assessment can be amended without going through the

When deciding if an error is to be corrected or not corrected, the decision-maker must consider the:

- particular facts and circumstances giving rise to the error, and

There is no required timeframe in order to correct an identified error.

Ms Sheehan advised that she was happy with the Administrative Review Tribunal s decision, but not

happy with the updated error correction that was implemented on 21 August 2024.

We applied the Administrative Review Tribunal s decision to set Mr Tierney s income for 3 years. We

then conducted an internal administrative review of how the decision was implemented onto the

case. An error was identified which was then corrected resulting in an overpayment of $6,454.

The AAT decision dated 24 January 2024 states in Paragraph 90 that income adjustments needed to be made for periods from 16 November 2022 to 30 June 2024.

It was identified that income for the period prior to 16 November 2022 was initially adjusted.

Once the error was identified, a review was conducted on the implementation of the ART decision

and adjustments were made in line with that decision.

After a review of how the decision was implemented as well as the correction of the identified error, we are satisfied Child Support have applied the Administrative Review Tribunal s decision

1. Ms Sheehan now seeks review by this Tribunal. She participated in the Tribunal's hearing by conference video. Mr Tierney participated in the hearing by conference telephone.
2. Mr Tierney's position, in simple terms, is that he considers the decision should be implemented correctly; he expressed no firm view about the Child Support position. Ms Sheehan's written application to the Tribunal advised the following:

CSV have disallowed my decision to object to the reversal

of the implementation of an AAT decision. I agree with AAT decision MC26285 and

the ATI's set for the paying parents income over a 3 year period, which resulted in an

increase of ~$400k of assessable income. I agreed with CSVs implementation of the

decision in Feb 2024 and I received a payment of $8218, of which $1724 related to [our

$6494 related to the ~$400k difference in income. The AAT decision expired in June

2024. In August 2024 CSV reverted the implementation and advised I had an

overpayment of $6454, my CS was stopped whilst i paid back this alleged debt. This

then negated the ATI's set by the AAT, and the paying parent has paid $40 for the

$400k difference in the paying parents income. This is unfair. To add insult to injury,

the paying parents self assessed income of $206k which triggered the original AAT

review was reinstated by CSV, despite the AAT's decision to set an ATI of $369k for

this period. The net result is that the ATI's set by the AAT were originally implemented

in Feb 2024 and then reversed out again in Aug 2024. The ATI's set by the AAT made

no difference to the CS that I received, other than increasing the paying parents

1. Ms Sheehan told the Tribunal she does not consider Child Support has now implemented the decision properly. She pointed to paragraph 91 of the decision where reference is made to several "child support periods", the first being identified as beginning on a January 2022. She submits the departure period was intended to start from that date, not 16 November 2022 as identified in paragraph 90.

1. It is trite to say that Child Support was obliged to correctly implement the Tribunal's decision of 24 January 2024. One description of this matter might be that there was merely a failed administrative action now rectified by the administrative action that ought to have been taken in the first place. In the absence of a new "decision" (and I note Child Support nor this Tribunal can "re-review" the decision of 24 January 2024), it might be suggested that there was no "decision" for the objections officer to review and, as a logical consequence, no decision for this Tribunal to now review.
2. I am inclined to the view that there is a decision in relation to the "particulars of the assessment".[1] The objections officer does not cite any source of power for the correction; I take that power to have been exercised pursuant to section 75 of the Child Support (Assessment) Act 1989 which gives a general discretion to amend any administrative assessment including for the purpose of correcting a mistake.
3. I understand Ms Sheehan's position. The headline decision read with paragraph 91 might be apt to confuse. However, it seems to me the Member citing the child support periods at paragraph 91 was simply a statement of fact concerning the assessment under the formula. The Member was required to compare the formula assessment with the proposed departure to determine if the proposed departure was just and equitable and otherwise proper. It is clear from paragraph 90 that the Member intended the departure to commence from 16 November 2022; that position is abundantly clear when read with paragraph 89:

The Tribunal finds that the start date for the departure from the assessment should be 16

November 2022, because while Ms Sheehan requested a change of assessment on 24

November 2022, she incurred the expense of [the child]'s orthodontic treatment on 16

November 2022,69 and the Tribunal cannot identify any special circumstances to

commence the departure determination from any date earlier than that. The Tribunal

concludes that the departure determination should end on 30 June 2024, as this is the end

of the financial year after the most recent information regarding Mr Tierney's income is

available and such a period of time provides some certainty.

1. Accordingly, I find that Child Support, on its own admission, incorrectly applied an adjustment to Mr Tierney's adjusted taxable income from 1 January 2022; that was subsequently corrected to apply only from 16 November 2022. The figures applied as Mr Tierney's adjusted taxable income have been properly restored to the (lower) assessments made under the child support formula.[2] Unfortunately for Ms Sheehan the consequence of that adjustment is that Mr Tierney's liability for 1 January 2022 to 15 November 2022 was wrongly assessed; the corollary of that error is an overpayment. Of course, Ms Sheehan was entitled to expect better; I note that Child Support has quite properly apologised for the way Ms Sheehan's matter was handled.
2. I am satisfied that Child Support has now correctly recorded the particulars of the assessment in accordance with this Tribunal's decision of 24 January 2024. As this is the same conclusion as the objections officer, the decision under review will be affirmed.
3. As a final observation, I note that if Ms Sheehan considers she has suffered a financial loss as a result of Child Support's admitted error (for example, incurring an interest expense in relation to the overpayment, or other related expense beyond mere expectation loss), she is at liberty to make an application to Child Support under the Commonwealth's compensation scheme.[3] I am very careful to observe that the Tribunal has no role or jurisdiction over that scheme.

[1] Section 80 of the Child Support (Registration and Collection) Act 1988 permits a person to object to the "particulars in the Child Support Register". Section 89 gives this Tribunal jurisdiction to review objection decisions.

[2] I note that the various decisions made during the period 1 January 2022 to 15 January 2022 (including the application of an estimated income) are decisions for which Ms Sheehan could have objected to within 28 days, or to seek an extension of time to bring an objection outside the 28-day period.

[3] The Compensation for Detriment caused by Defective Administration (CDDA) Scheme.