Broken Places by Tracy Clark

Former cop Cass Raines has found the world of private investigation a less stressful way to eke out a living in the Windy City. But when she stumbles across the dead body of a respected member of the community, it's up to her to prove a murderer is on the loose . . .

Cops can make mistakes, even when they're not rookies. If anyone knows that it's Cass Raines, who took a bullet two years ago after an incompetent colleague screwed up a tense confrontation with an armed suspect. Deeply traumatized by the incident, Cass resigned from the Chicago PD, leaving one less female African-American on the force. Now she's the head of a one-woman private investigation agency, taking on just enough work to pay the bills. She spends the rest of her time keeping an eye on the tenants in her little Hyde Park apartment building, biking along the lakefront, and playing chess with the only father figure she's ever known, Father Ray Heaton.

When Father Ray asks Cass to...