The following problems require reasoning for their solution. To prove that an answer is correct requires an argument (often containing subsidiary arguments) whose premises are contained in the statement of the problem—and whose final conclusion is the answer to it. If the answer is correct, it is possible to construct a valid argument proving it. In working these problems, readers are urged to concern themselves not merely with discovering the answers but also with formulating arguments to prove that those answers are correct.

Daniel Kilraine was killed on a lonely road, 2 miles from Pontiac, Michigan, at 3:30 A.M. on March 17 of last year. Otto, Curly, Slim, Mickey, and the Kid were arrested a week later in Detroit and questioned. Each of the five made four statements, three of which were true and one of which was false. One of these persons killed Kilraine.

Their statements were:

Otto: I was in Chicago when Kilraine was murdered. I never killed anyone. The Kid is the guilty one. Mickey and I are pals.
Curly: I did not kill Kilraine. I never owned a revolver in my life. The Kid knows me. I was in Detroit the night of March 17.
Slim: Curly lied when he said he never owned a revolver. The murder was committed on St. Patrick’s Day. Otto was in Chicago at this time. One of us is guilty. 

Mickey: I did not kill Kilraine. The Kid has never been in Pontiac. I never saw Otto before. Curly was in Detroit with me on the night of March 17.
The Kid: I did not kill Kilraine. I have never been in Pontiac. I never saw Curly before. Otto erred when he said I am guilty.

Whodunnit?