The guardians

In the small Florida town of Seabrook, a young lawyer named Keith Russo is shot dead at his desk as he works late one night. The killer leaves no clues. There are no witnesses, no one with a motive. But the police soon come to suspect Quincy Miller, a young black man who was once a client of Russo's. Quincy is tried, convicted, and sent to prison for life. For twenty-two years he languishes in prison, maintaining his innocence.
But no one listens. He has no lawyer, no advocate on the outside. In desperation, he writes a letter to Guardian Ministries, a small nonprofit run by Cullen Post, a lawyer who is also an Episcopal minister. Guardian accepts only a few innocence cases at a time. Cullen Post travels the country fighting wrongful convictions and taking on clients forgotten by the system. With Quincy Miller, though, he gets far more than he bargained for.
Powerful, ruthless people murdered Keith Russo, and they do not want Quincy Miller exonerated. They killed one lawyer twenty-two years ago, and they will kill another without a second thought.

Source : Anchor Books