Scotland's working-age Council Tax Reduction uses the Child Benefit young person, not the Universal Credit one (SSI 2021/249 reg 6) #2286

What is wrong

Scotland's working-age Council Tax Reduction scheme defines a "young person" as a Universal Credit qualifying young person. The model uses the Child Benefit definition for every scheme: council_tax_reduction_applicable_amount decides lone-parent status with is_lone_parent, and council_tax_reduction_applicable_income counts the income of is_child_or_young_person_for_legacy_benefits members. Both follow the Child Benefit qualifying young person.

The two definitions differ. For example, a 19-year-old on a non-advanced course begun before 19 is a Child Benefit qualifying young person until 20 (Child Benefit (General) Regulations 2006 reg. 3), but a Universal Credit one only until the 1 September after their 19th birthday (UC Regs 2013 reg. 5(1)(b)).

On main (9475c95), 2026-27, a single claimant aged 22 in Edinburgh, not on Universal Credit, with a 19-year-old at school who is past that 1 September and earns £2,000:

• council_tax_reduction_applicable_amount = £4,968.60, the lone parent allowance (£95.55 × 52). It should be £3,933.80, the single under-25 allowance (£75.65 × 52).
• council_tax_reduction_applicable_income = £3,406.60, which counts the 19-year-old's £2,000. It should be £1,406.60.

The law

Council Tax Reduction (Scotland) Regulations 2021 (SSI 2021/249), in force 1 April 2022 (reg. 1):

• Reg. 6(1): "In these Regulations “young person” means a person who falls within the definition of “qualifying young person” in regulation 5 of the 2013 Regulations (meaning of qualifying young person)." Reg. 4 defines "the 2013 Regulations" as the Universal Credit Regulations 2013.
• Reg. 4: "“lone parent” means a person who has no partner and who is responsible for and a member of the same household as a child or young person".
• Reg. 7(2)-(3): "A person is responsible for a child or young person who normally lives with them. But a person is not responsible for a young person if the two of them are living as a couple."

The other schemes keep the Child Benefit definition, so they are right today:

• Scotland, pension age: SSI 2012/319 reg. 4(1), "a person who falls within the definition of “qualifying young person” in section 142 of the 1992 Act".
• England: SI 2012/2885 reg. 2. Wales: WSI 2013/3029 reg. 2.
• Scotland, working age, to 31 March 2022: SSI 2012/303 reg. 4 as made.

Fix

Give Council Tax Reduction its own child-or-young-person flag: the Universal Credit test in Scotland's working-age scheme from 2022-23, and the legacy (Child Benefit) flag elsewhere. Read it for lone-parent status in the applicable amount and for the members whose income counts.

Found as a follow-up to #2279. #1966 (draft) builds new Scottish working-age variables on is_lone_parent and the legacy flag; it should read the new flag once this lands.