Causality Chain · Audit Detail
HOLC Redlining + FHA Mortgage Segregation
white_flight_redlining · order-3 · AP HuG subtopic 6.5 · status rated
A
Composite 12.00 / confidence high
Grade A: 3 sources, source_quality_avg=5.00, corroboration=3, claim_strength=2, geo_specific=1, counter_evidence_handled=no.
The historical event
HOLC Redlining + FHA Mortgage Segregation · 1937 · US metropolitan areas
Home Owners' Loan Corporation maps (1937+) classified Black neighborhoods as 'hazardous' → FHA refused mortgages → 80-year residential segregation pattern persists.
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Causal trigger + effect
Trigger
Card(s):
edge_cityConditions:
{'requires_held_card': 'ethnic_enclave'}Threshold:
—Effect
Type:
cst_delta_neighborsPayload:
{'delta': -1, 'reason': 'segregation_cost'}Target: neighbors
Delay turns: 1
Methodology subscores
| Dimension | Score |
|---|---|
| Source quality (avg) | 5.0 |
| Corroboration (independent sources) | 3 |
| Causal-claim strength | 2 |
| Counter-evidence handling | 0 |
| Geographic specificity | 1 |
| Temporal scope | 1 |
Primary sources (3)
Rothstein, R., 'The Color of Law: A Forgotten History of How Our Government Segregated America', Liveright 2017
Type:
peer_reviewed · Year: 2017 · Geography: United StatesComprehensive synthesis of federal segregation policy; HOLC + FHA + zoning + Levittown.
Sugrue, T., 'The Origins of the Urban Crisis: Race and Inequality in Postwar Detroit', Princeton UP 1996
Type:
peer_reviewed · Year: 1996 · Geography: DetroitCase study of postwar segregation + deindustrialization interplay; Bancroft Prize winner.
Aaronson, D. et al., 'The Effects of the 1930s HOLC Redlining Maps', AEJ Economic Policy 13(4) 2021
Type:
peer_reviewed · Year: 2021 · Geography: 239 US citiesQuasi-experimental causal estimate: HOLC maps caused persistent 80-year racial composition + homeownership gaps.
Counter-evidence (0)
No counter-evidence noted. Trellison reserves the right to escalate this chain to "needs counter-evidence review" if challenges emerge.
Audit metadata
Audit ID:
c09735ef743e4d678dd052b3d26e92d7Audit date: 2026-05-14T05:54:32.703725+00:00
Protocol version:
v1.0Rater: claude_sprint2_auto
Corroborating independent count: 3