The Harried Hairdresser - The Hot Dog Detective - A Denver Detective Cozy Mystery, #8

MacFarland knew in his heart that Scott Porter really was guilty.The problem was, he had promised his sister-in-law that he would find a way to prove the man innocent. All he had to do was find out who really killed the man's wife, Amanda. But as every cop knew, it usually was the husband. Then, when the first of several homeless men were discovered killed in the same way as Amanda had been, MacFarland realized he was dealing with a serial killer.
What was the connection between the pretty socialite, Amanda Porter, and a bunch of homeless men? And why couldn't MacFarland shake the feeling that Scott Porter had something to do with all the deaths?