Rusty and the Nuclear Family

Rusty thinks he has a lead on the real perp, but instead he ends up discovering that the judge presiding over his trial is part of a payoff scheme. Rusty's wife killed the mistress and set it up to look like Rusty did it, to get revenge for his affair. The movie ends with Rusty's voiceover telling us that even though he now knows his wife is evil, he is going to stay with her in order to spare their teenage son the trauma of divorce. Keeping the family together is so important that it justifies murder.