Of the writers who deal with mystery and murder as seen through the eyes of a priest, Ralph McInerny and William X. Kienzle are probably the two leading American practitioners…. Mr. Kienzle's man is Father Robert Koesler in Detroit. He first appeared in "The Rosary Murders," which attracted a good deal of attention. Now Father Koesler is back, in ["Death Wears a Red Hat"]….
Basically the book is a procedural. Father Koesler works with the police. But the thrust of the book is religious, with many observations about Catholicism in the modern world. The murders can be solved only by someone with a Catholic background. And very perplexing murders they are. Somebody is hacking the heads off victims and putting them on statues in churches. It so happens that all of the victims are villains, and there are those in Detroit who want to give the murderer the keys to the city….
The situation is highly contrived. "Death Wears a Red Hat" is in some respects a throwback to the Ellery Queen mysteries—ingenious but improbable. Also improbable is the modus operandi that the author asks the reader to accept. But the ending is interesting, and contains a moral problem that confuses the law enforcement people. When is a murder not a murder? "Death Wears a Red Hat" will not bore you. The book is well written and has some well-drawn characters, including a pair of competing reporters and some believable cops. And priests, all over the place, who play golf, specialize in arcane church lore, pass themselves off as restaurant critics (at least, one of them does), argue and complain.
Newgate Callendar, "Crime: 'Death Wears a Red Hat'," in The New York Times Book Review (© 1980 by The New York Times Company; reprinted by permission), June 15, 1980, p. 17.