In 2012, a Chicago police sergeant and an officer were arrested in an undercover operation for stealing $5,200 from a person carrying what they thought was cash for drug dealers. The officers eventually entered plea deals, but the arrests led to scrutiny of the tactics they and their team had used while making drug arrests at the Ida B. Wells housing complex on Chicago’s South Side for years.

This week, 14 men with drug convictions related to those cases were exonerated — four of them on Wednesday and 10 on Monday. With those exonerations, 63 men and women have had their cases vacated because of the involvement of Sgt. Ronald Watts and Officer Kallatt Mohammed, lawyers for the 14 men said.

“It is a stain on the city,” said Joshua Tepfer, a lawyer with the University of Chicago Law School’s Exoneration Project, which has represented 47 of the 63 people exonerated.

“One thing that goes without saying is the reason they were covered up is they were viewed as a disposable people who live in the housing projects,” he said. “Nobody cared. Nobody believed them.”