The police procedural is governed by technique. Its essence is the following of the techniques used by professional law enforcement officers to solve crimes. Thus most of The Fourth Deadly Sin involves the step-by-step procedures of identifying suspects, interviewing them, tracking down witnesses, and ferreting out clues. Sanders gives his detectives three mysteries to solve: 1) Who killed Ellerbee? 2) What was the motive for killing Ellerbee? 3) What accounts for the two separate tracks of wet footprints to the office of Ellerbee? If there is a weakness to the novel, it is that the experienced reader of mysteries is likely to figure out the answers early on. On the other hand, the pleasure of the book, as it is for other police procedurals, is following how the police solve a case.

Sanders is very good at describing settings, and his portraits of locales as diverse decaying slums and upscale gay...