Use one carer attribution for the legacy severe disability premium and the Pension Credit addition (stacked on #1946 and #1951)

changelog.d/sdp-carer-attribution.fixed.md

@@ -0,0 +1 @@
+The legacy severe disability premium and the Pension Credit severe disability addition now share one attribution of whom each carer benefit is paid for caring for (`is_cared_for_by_carer_benefit_recipient`), so a carer in another benefit unit of the household bars the legacy premium as it already barred the addition, even when that carer is ignored as a non-dependant.

policyengine_uk/parameters/gov/dwp/carers_allowance/qualifying_disability_benefits.yaml

@@ -0,0 +1,31 @@
+description: >
+  Benefits whose receipt makes a person severely disabled for Carer's
+  Allowance, so that a carer benefit may be paid for caring for them:
+  attendance allowance, the care component of disability living allowance at
+  the highest or middle rate, the daily living component of personal
+  independence payment and armed forces independence payment. The Scottish
+  equivalents are not separate model variables, and the constant attendance
+  allowances prescribed by regulation 3 of the Invalid Care Allowance
+  Regulations are not modelled.
+metadata:
+  label: Carer's Allowance qualifying disability benefits
+  period: year
+  unit: list
+  reference:
+    - title: Social Security Contributions and Benefits Act 1992 s. 70(2)
+      href: https://www.legislation.gov.uk/ukpga/1992/4/section/70
+    - title: The Personal Independence Payment (Supplementary Provisions and Consequential Amendments) Regulations 2013 Sch. para. 5
+      href: https://www.legislation.gov.uk/uksi/2013/388/schedule/paragraph/5
+    - title: "The Armed Forces and Reserve Forces (Compensation Scheme) (Consequential Provisions: Primary Legislation) Order 2013 art. 3(2)"
+      href: https://www.legislation.gov.uk/uksi/2013/796/article/3
+    - title: The Social Security (Invalid Care Allowance) Regulations 1976 reg. 3
+      href: https://www.legislation.gov.uk/uksi/1976/409/regulation/3
+values:
+  1992-07-01:
+    - attendance_allowance
+    - dla_sc_middle_plus
+  2013-04-08:
+    - attendance_allowance
+    - dla_sc_middle_plus
+    - pip_dl
+    - armed_forces_independence_payment

policyengine_uk/tests/policy/baseline/finance/benefit/family/severe_disability_premium.yaml

@@ -520,6 +520,190 @@
   output:
     severe_disability_premium: [4474.60, 0]
 
+# Carers in other benefit units (para 14(2)(a)(iii) and (2)(b), with 14(4)).
+# The carer condition is separate from the non-dependant condition: a
+# non-dependant whose presence is ignored under para 14(4) can still be the
+# person who receives a carer benefit for caring for the claimant. Whom each
+# carer benefit is paid for is attributed by
+# is_cared_for_by_carer_benefit_recipient, shared with the Pension Credit
+# severe disability addition.
+
+- name: A non-dependant ignored for receiving a qualifying benefit still bars the premium as the claimant's carer
+  period: 2026
+  absolute_error_margin: 0.01
+  input:
+    people:
+      claimant:
+        age: 50
+        pip_dl_category: STANDARD
+      son:
+        age: 25
+        pip_dl_category: STANDARD
+        receives_carer_benefit: true
+    benunits:
+      claimant_family:
+        members: [claimant]
+      son_family:
+        members: [son]
+    households:
+      household:
+        members: [claimant, son]
+  output:
+    # Each is ignored as the other's non-dependant (para 14(4)(a)). The son's
+    # Carer's Allowance is for caring for the claimant, so the claimant fails
+    # para 14(2)(a)(iii); no one is paid for caring for the son.
+    has_non_dependant_for_severe_disability_premium: [false, false]
+    is_cared_for_by_carer_benefit_recipient: [true, false]
+    severe_disability_premium: [0, 4474.60]
+
+- name: A blind non-dependant who receives a carer benefit bars the premium
+  period: 2026
+  absolute_error_margin: 0.01
+  input:
+    people:
+      claimant:
+        age: 50
+        pip_dl_category: STANDARD
+      son:
+        age: 25
+        is_blind: true
+        receives_carer_benefit: true
+    benunits:
+      claimant_family:
+        members: [claimant]
+      son_family:
+        members: [son]
+    households:
+      household:
+        members: [claimant, son]
+  output:
+    # The son is ignored as a non-dependant (para 14(4)(b)) but is the
+    # claimant's carer.
+    has_non_dependant_for_severe_disability_premium: [false, false]
+    is_cared_for_by_carer_benefit_recipient: [true, false]
+    severe_disability_premium: [0, 0]
+
+- name: A couple who both qualify get the single rate when an ignored non-dependant is paid for caring for one of them
+  period: 2026
+  absolute_error_margin: 0.01
+  input:
+    people:
+      claimant:
+        age: 50
+        pip_dl_category: STANDARD
+      partner:
+        age: 48
+        pip_dl_category: ENHANCED
+      son:
+        age: 25
+        pip_dl_category: STANDARD
+        receives_carer_benefit: true
+    benunits:
+      couple:
+        members: [claimant, partner]
+      son_family:
+        members: [son]
+    households:
+      household:
+        members: [claimant, partner, son]
+  output:
+    # One award is for one person: a carer for only one of the couple leaves
+    # the single rate (para 14(2)(b); Sch 3 para 20(6)(b)(i)).
+    is_cared_for_by_carer_benefit_recipient: [true, false, false]
+    severe_disability_premium: [4474.60, 4474.60]
+
+- name: A non-dependant who receives a carer benefit and has a severely disabled partner is treated as caring for their partner
+  period: 2026
+  absolute_error_margin: 0.01
+  input:
+    people:
+      claimant:
+        age: 50
+        pip_dl_category: STANDARD
+      son:
+        age: 30
+        pip_dl_category: STANDARD
+        receives_carer_benefit: true
+      sons_partner:
+        age: 28
+        pip_dl_category: STANDARD
+    benunits:
+      claimant_family:
+        members: [claimant]
+      son_family:
+        members: [son, sons_partner]
+    households:
+      household:
+        members: [claimant, son, sons_partner]
+  output:
+    # A carer cares within their own benefit unit first, so the claimant has
+    # no carer. The son and his partner both qualify with a carer paid for
+    # one of them: the single rate.
+    is_cared_for_by_carer_benefit_recipient: [false, false, true]
+    severe_disability_premium: [4474.60, 4474.60]
+
+- name: One carer's award bars the premium of only one of two other benefit units, the one with the eldest member
+  period: 2026
+  absolute_error_margin: 0.01
+  input:
+    people:
+      older:
+        age: 60
+        pip_dl_category: STANDARD
+      younger:
+        age: 55
+        pip_dl_category: STANDARD
+      carer:
+        age: 30
+        pip_dl_category: STANDARD
+        receives_carer_benefit: true
+    benunits:
+      older_family:
+        members: [older]
+      younger_family:
+        members: [younger]
+      carer_family:
+        members: [carer]
+    households:
+      household:
+        members: [older, younger, carer]
+  output:
+    is_cared_for_by_carer_benefit_recipient: [true, false, false]
+    severe_disability_premium: [0, 4474.60, 4474.60]
+
+- name: The legacy premium and the Pension Credit addition read the same carer attribution
+  period: 2026
+  absolute_error_margin: 0.01
+  input:
+    people:
+      pensioner:
+        age: 70
+        aa_category: LOWER
+      working_age:
+        age: 45
+        pip_dl_category: STANDARD
+      carer:
+        age: 40
+        pip_dl_category: STANDARD
+        receives_carer_benefit: true
+    benunits:
+      pensioner_family:
+        members: [pensioner]
+      working_age_family:
+        members: [working_age]
+      carer_family:
+        members: [carer]
+    households:
+      household:
+        members: [pensioner, working_age, carer]
+  output:
+    # The one carer benefit is for the pensioner under both rules, so the
+    # working-age claimant keeps the premium and the pensioner loses the
+    # addition.
+    is_cared_for_by_carer_benefit_recipient: [true, false, false]
+    severe_disability_premium: [0, 4474.60, 4474.60]
+    severe_disability_minimum_guarantee_addition: [0, 4474.60, 4474.60]
+
 # Flow-through to the applicable amounts.
 
 - name: The premium is part of the legacy benefit premiums

policyengine_uk/tests/policy/baseline/gov/dwp/pension_credit/guarantee_credit/severe_disability_residence_and_carers.yaml

@@ -4,7 +4,8 @@
 # (para 1(1)(a)(iii), (b)(ii) and (c)(iv)). 2026-27 weekly rates: one rate
 # 86.05 (4,474.60 a year), two rates 172.10 (8,949.20 a year).
 # Carer benefits are attributed as documented on
-# num_severe_disability_addition_qualifiers_cared_for.
+# is_cared_for_by_carer_benefit_recipient, which the legacy severe disability
+# premium shares.
 
 - name: A single claimant on Attendance Allowance who lives alone gets one rate
   period: 2026
@@ -212,7 +213,7 @@
         country: ENGLAND
   output:
     receives_carer_benefit: true
-    num_severe_disability_addition_qualifiers_cared_for: 0
+    is_cared_for_by_carer_benefit_recipient: false
     severe_disability_minimum_guarantee_addition: 4_474.60
 
 - name: Carer's Allowance paid to another household member stops a single claimant's addition
@@ -241,7 +242,7 @@
         members: [claimant, daughter]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: [1, 0]
+    is_cared_for_by_carer_benefit_recipient: [true, false]
     severe_disability_minimum_guarantee_addition: [0, 4_474.60]
 
 - name: A couple who both qualify get one rate when the claimant receives Carer's Allowance
@@ -267,7 +268,7 @@
         members: [claimant, partner]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: 1
+    is_cared_for_by_carer_benefit_recipient: [false, true]
     severe_disability_minimum_guarantee_addition: 4_474.60
 
 - name: A couple who both qualify get one rate when another household member receives Carer's Allowance
@@ -296,7 +297,7 @@
         members: [claimant, partner, daughter]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: [1, 0]
+    is_cared_for_by_carer_benefit_recipient: [true, false, false]
     severe_disability_minimum_guarantee_addition: [4_474.60, 4_474.60]
 
 - name: A couple get nothing when carer benefits are paid for both partners
@@ -329,7 +330,7 @@
         members: [claimant, partner, daughter]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: [2, 0]
+    is_cared_for_by_carer_benefit_recipient: [true, true, false]
     severe_disability_minimum_guarantee_addition: [0, 4_474.60]
 
 - name: A qualifying partner's own Carer's Allowance does not stop the blind-partner route
@@ -356,7 +357,7 @@
         members: [claimant, partner]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: 0
+    is_cared_for_by_carer_benefit_recipient: [false, false]
     severe_disability_minimum_guarantee_addition: 4_474.60
 
 - name: The blind-partner route also needs no other adult resident
@@ -649,7 +650,7 @@
         members: [younger, elder, carer]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: [0, 1, 0]
+    is_cared_for_by_carer_benefit_recipient: [false, true, false]
     severe_disability_minimum_guarantee_addition: [4_474.60, 0, 0]
 
 - name: Two carers in the household cover two benefit units
@@ -685,7 +686,7 @@
         members: [younger, elder, carer_1, carer_2]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: [1, 1, 0, 0]
+    is_cared_for_by_carer_benefit_recipient: [true, true, false, false]
     severe_disability_minimum_guarantee_addition: [0, 0, 0, 0]
 
 - name: Two single pensioners who each receive Carer's Allowance care for each other
@@ -713,7 +714,7 @@
         members: [first, second]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: [1, 1]
+    is_cared_for_by_carer_benefit_recipient: [true, true]
     severe_disability_minimum_guarantee_addition: [0, 0]
 
 - name: A resident who has just attained 18 and is not a qualifying young person counts
@@ -772,6 +773,7 @@
         members: [first, second, third]
         country: ENGLAND
   output:
+    is_cared_for_by_carer_benefit_recipient: [true, true, true]
     severe_disability_minimum_guarantee_addition: 0
 
 - name: A carer whose own disabled child qualifies is treated as caring for the child
@@ -804,7 +806,7 @@
         members: [grandmother, daughter, child]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: [0, 0]
+    is_cared_for_by_carer_benefit_recipient: [false, false, true]
     severe_disability_minimum_guarantee_addition: [4_474.60, 4_474.60]
 
 - name: A second carer in a pensioner's unit is attributed to a pensioner in another unit
@@ -839,7 +841,7 @@
         members: [first, carer_1, carer_2, second]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: [1, 1]
+    is_cared_for_by_carer_benefit_recipient: [true, false, false, true]
     severe_disability_minimum_guarantee_addition: [0, 0]
 
 - name: When two benefit units' eldest members are the same age, the one whose eldest member comes first in person order takes a carer
@@ -869,7 +871,7 @@
         members: [listed_first, listed_second, carer]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: [1, 0, 0]
+    is_cared_for_by_carer_benefit_recipient: [true, false, false]
     severe_disability_minimum_guarantee_addition: [0, 4_474.60, 0]
 
 - name: A carer who is the only qualifying member of their own unit cares for someone in another unit
@@ -903,7 +905,7 @@
         members: [grandmother, father, daughter]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: [1, 0]
+    is_cared_for_by_carer_benefit_recipient: [true, false, false]
     severe_disability_minimum_guarantee_addition: [0, 0]
 
 - name: The two young carers cover both pensioners when each is in their own unit too
@@ -941,5 +943,5 @@
         members: [first, carer_1, carer_2, second]
         country: ENGLAND
   output:
-    num_severe_disability_addition_qualifiers_cared_for: [1, 0, 0, 1]
+    is_cared_for_by_carer_benefit_recipient: [true, false, false, true]
     severe_disability_minimum_guarantee_addition: [0, 0, 0, 0]