DL v Secretary of State for Work and Pensions & Anor

A purported child-support supersession decision must decide more than whether a child is a qualifying child. It must determine whether maintenance is payable, its amount, its effective date and the basis of calculation. Correspondence which supplies only one component does not amount to a decision under Child Support Act 1991 section 17 and cannot found an appeal.

A failure to comply with notification requirements does not invariably produce total invalidity. The statutory purpose, substantial compliance and relevant prejudice may be considered. However, a notice that omits both the sum payable and the basis of assessment lacks substantive compliance and is invalid.

The appellant was the non-resident parent of twins. The second respondent sought to add one twin, C, to an existing child-maintenance calculation after C came to live with her and was said to be in full-time education.

The Child Maintenance Service sent various letters and made internal records, but did not notify a maintenance amount or calculation. It later cancelled a service request. The First-tier Tribunal treated the correspondence cumulatively as notification of a supersession decision and allowed the second respondent's appeal.

The appellant appealed to the Upper Tribunal. The central issue was whether there had been an appealable supersession decision and, alternatively, whether defective notification could be relied upon.

1. Appeal allowed. The First-tier Tribunal erred in law. Its decision was set aside and remade by striking out the second respondent's appeal because there was no appealable decision.

2. The second respondent's request to add C to an existing calculation was an application for a supersession under section 17 of the Child Support Act 1991, rather than a fresh application for a maintenance calculation. A decision in that context had to determine whether child support maintenance was payable and, if so, how much, from when, and on what basis.

3. The March 2021 correspondence did not make such a decision. At most, it indicated that C might be a qualifying child in education. It did not state the maintenance amount, effective date or calculation. The First-tier Tribunal was wrong to construct a decision by combining separate communications which did not satisfy the statutory scheme.

4. The internal cancellation of a service request could not be treated as a refusal of the supersession application. It was unexplained, was not communicated to either party, and did not itself constitute a decision.

5. In the alternative, the judge held that notification requirements may generally admit of substantial compliance. The court must first construe the legislation to decide whether Parliament intended total invalidity. If not, it considers the circumstances, including compliance in substance and relevant prejudice. This was an administrative decision-making context. Nevertheless, omission of both the amount payable and the basis of assessment was fundamental. The notification was invalid rather than merely deficient.

6. Remittal was inappropriate. The absence of a decision meant that there was only one proper outcome. The Secretary of State might consider making a lawful supersession decision to resolve any continuing dispute.

• Upper Tribunal (Administrative Appeals Chamber): Allowed the appellant's appeal, set aside the First-tier Tribunal's decision and remade it by striking out the underlying appeal: [2025] UKUT 108 (AAC).
• First-tier Tribunal (Social Entitlement Chamber): Treated the Child Maintenance Service correspondence as notification of a supersession decision and determined that maintenance was payable for C. The decision was dated 6 February 2023 in the Upper Tribunal's reasons.