True Blue by David Baldacci

Baldacci introduces two new characters, sisters Beth and Mace Perry. Beth is the chief of police in Washington, DC and Mace is her disgraced younger sister. Mace is just out of prison and determined to prove she was framed. She also wants to solve a big case because she believes that is her ticket to being reinstated as a police officer, or "true blue." When a lawyer is found dead and stuffed in a refrigerator, Mace begins her own investigation. This is a Baldacci book, so nothing is simple, shadowy government agencies are involved, and someone powerful is corrupt. I'm sure this isn't the last we'll see of Beth and Mace Perry, and I'm glad.