Run, Killer, Run - William Gault Campbell

Ex-bookie Tom Spears, framed for the murder of his wife, breaks out of prison and heads for Mexico and freedom. En route, he learns that the lawyer (and friend) who defended him has been murdered. He also discovers that his beloved wife had been unfaithful, that his lawyer friend had been one of her lovers, and that his defense had been deliberately botched. Resolving to unravel the mystery, Spears becomes entangled with his former associates and finds himself caught up in the crossfire between rival gambling syndicates.