The History of Redlining in Connecticut and the Country, Andrew Ba Tran, TrendCT, October 27, 2016, available here

In the ’30s and ’40s during the Great Depression, federal officials and local lenders rated mortgage risk in hundreds of cities based on physical conditions, as well as the race and ethnicity and social classes within neighborhoods. The agency color-coded neighborhoods on the potential credit risk they posed based on outdated assumptions. This real-estate practice of “redlining” led to decades of government-sanctioned housing and loan discrimination.