The mayor of Memphis, A C Wharton Jr., has walked with bile rising in his throat through the streets of Hickory Hill and Orange Mound and Whitehaven in recent years, as house after house in those black neighborhoods has fallen into foreclosure.

On Wednesday, Mr. Wharton and other city and county officials filed a lawsuit accusing one of the nation’s largest banks, Wells Fargo, of singling out black homeowners for high-interest subprime mortgages.

The lawsuit, filed in federal court in Tennessee, marshaled a raft of statistics to argue that Wells Fargo offered one lending reality for whites and another for blacks. In Shelby County, which includes Memphis, one of every eight Wells Fargo loans in predominantly black neighborhoods resulted in foreclosure, compared with only one in 59 such loans in white neighborhoods, the lawsuit said.

Such charges, if proven, amount to reverse redlining  marketing expensive loan products specifically to black customers.