Resource · Updated 07/07/2026
Case law digest
Upper Tribunal decisions bind the CMS and the First-tier Tribunal. Cited accurately, they transform an argument from opinion into authority. Full texts are free on BAILII; more recent decisions also appear on GOV.UK. Always read the full decision before citing it — headnotes mislead.
Variations and diversion of income
PP v SSWP and SP (CSM) [2022] UKUT 286 (AAC)
What it decided: the "just and equitable" requirement in s.28F CSA 1991 confers a broad discretion; variations are not all-or-nothing, and a tribunal cannot simply set a diversion variation at the maximum a company could theoretically have paid in dividends. Also a fair-hearing authority: parties must have a proper opportunity to deal with the material relied on.
Use it when: a variation decision (either way) was made mechanically, without weighing the circumstances, or a tribunal speculated rather than found facts. Full text.
KW v SSWP and KE (CSM) [2017] UKUT 400 (AAC)
What it decided: guidance on when pension contributions amount to diversion of income — the question is whether the paying parent has unreasonably reduced the income taken into account, considering size, pattern and purpose of contributions.
Use it when: pension contributions look disproportionate (receiving parents), or your ordinary contributions are being attacked as diversion (paying parents). Full text.
AS v SSWP (CSM) [2018] UKUT 315 (AAC)
What it decided: analysis of the diversion ground where income is routed to third parties or purposes under the paying parent's control; findings must rest on evidence of control and unreasonable reduction, not inference from lifestyle alone.
Use it when: arguing (or resisting) diversion built on company structures or family payments. Full text.
Tribunal role and procedure
HH v SSWP and ASP (CSM) [2021] UKUT 280 (AAC)
What it decided: the FtT is an expert fact-finding body that considers variation evidence afresh — it is not confined to reviewing what the CMS did, and is often better placed to determine additional income.
Use it when: the CMS says "we couldn't verify it, so nothing can be done" — the tribunal can, and this is the authority. Full text.
Special expenses
LM v SSWP and NM (CSM) [2024] UKUT 259 (AAC)
What it decided: current guidance on the prior-mortgage special expenses ground — the conditions under which a paying parent's payments on the former family home reduce the maintenance calculation.
Use it when: you pay the mortgage on a home you left, in which the receiving parent and children still live, and hold no interest in it. Search GOV.UK decisions; commentary at the Financial Remedies Journal.
How to cite in an MR or appeal
Name, citation, and the point: "The refusal treats the variation as all-or-nothing, contrary to PP v SSWP (CSM) [2022] UKUT 286 (AAC), which requires the just-and-equitable discretion to be exercised on the whole circumstances." Attach the relevant pages of the decision to your bundle. One accurate authority beats five vague ones.
This digest is a starting point, not a complete statement of the law. Decisions are added as they are verified; suggest additions via the about page.
Sources
| Source | Type | Date | Credibility |
|---|---|---|---|
| BAILII — UT (AAC) decisions | Primary (law reports) | Ongoing | High |
| GOV.UK — Administrative Appeals Tribunal decisions | Primary (official database) | Ongoing | High |
| Financial Remedies Journal — LM v SSWP commentary | Practitioner commentary | 2024 | Medium — specialist journal |