True Blue by David Baldacci

True Blue - Mace Perry was a cop with the D.C. police force until she was framed for a crime which she has been imprisoned. When she gets out, she is determined to either solve a big crime to prove her innocence. Her sister, the police chief, tries to help while a US attorney is determined to send her back to jail. Roy Kingman, a lawyer in a prestigious firm in D.C., finds the body of a coworker in the company refrigerator. Mace & Roy work together to solve the murder.