Ah, Treachery! - Ross Thomas

Ah, Treachery!, the last novel Thomas wrote before his death, tells the story of one Captain Edd "Twodees" Partain, drummed out of the Army and hounded by rumors of his involvement in a secret operation in El Salvador. Twodees gets hired on to help a fundraiser for the "Little Rock folks" recover funds that were stolen from an illicit stash used to smooth over problems and pay off hush money. Meanwhile, Partain is involved in a storefront operation called VOMIT (Victims of Military Intelligence Treachery) trying to defend former intelligence operatives such as Partain from those who are trying to cover up the past permanently.