Nothing's Certain But Death - A Conan Flagg Mystery, #4

There he lay in a freezer-the late Eliot Nye, IRS auditor. He had been investigating Brian Tally, owner of Surf House Restaurant, for tax fraud. He was last seen alive late the evening before when he had burst in on a boisterous party at the Surf House bar where Tally swung at him. Tally was the obvious suspect, but Conan Flagg, bookstore owner and amateur detective, discovered enough strong passion among Surf House staffers to make any of them kill. The big problem was that Nye left a message pointing straight to Tally as his killer.
Flagg was stuck with refuting the irrefutable.and pinning the ugly crime on the real killer. "A fascinating mystery."Minneapolis Star & Tribune