Guilty as Sin (1993) on Netflix

A man accused of murdering his wife approaches a hotshot female criminal attorney to take his case. The man is a self-professed womaniser, and his alleged motive would be the large sum of money his wife left him. The attorney begins to have second thoughts about representing him when he starts making it look like they're having an affair and tells her things she can't reveal because of lawyer/client privilege, so she starts her own investigation of him, which threatens her career and the safety of her friends and herself.