If your spouse committed murder and he or she confided in you would you turn them in:
Yes, I would turn my spouse in. Who is to say that if they killed once that they wont kill again. Who is to say that you aren't there next target. If they were to ever become paranoid about being caught they might just blow out your brains because paranoia makes you do crazy things. It would be hard to turn them in because you have a deep connection with your spouse but it's something you have to do for your own safety.