Hog Heaven (S09E23)

A brutal motorcycle gang murder takes place in a biker bar. There are multiple suspects because of the nature of the killing. It turns out that an undercover cop has infiltrated this gang, and is very close to exposing a major drug operation they are running. The UC's wife is called in for questioning when it becomes clear that she is unstable and hitting the bottle. Not only is she a suspect, but she is an ex-lover of Brass. Brass becomes emotionally involved in the case and tries to exonerate this woman. In the end, it was her drunken phone call to the biker bar that got her husband murdered. (CBS TV Network)