Police in Detroit have arrested a man, Henry Allen Michael, 47, who allegedly killed his son-in-law that walked in on him, while having sex with his daughter.
The man who was only 25-year-old got into the argument when he saw the horrible scene, he was then stabbed in the back by the father-in-law when he tried walking away from the room.
The woman who was having sex with his dad denied ever knowing what happened as she had passed out after going out to have some drinks with her dad