They were trespassing and were right up ON his house at 1am, so I think it's believeable that he thought they may have been burglars or worse. Therefore, I think that he was justified in using deadly force to protect his property and/or himself and his family. However, I have seen this type of thing play out AGAINST a homeowner before, up close and personal. When I was about 13 one of our neighbors shot and killed a teen who was attemtping to break into his back door in the middle of the night. It turned out that he was a classmate of his daughter and he had overheard her say that they were going on a famblee camping trip that weekend, but her dad hadn't felt well so he had stayed at home. The dad had ALSO drank a good deal of scotch that night which was held against him at trial. He had called the police and said there was an intruder, he claimed to have yelled at the intruder and warned him he had a gun and that the police had been called, and then he said the intruder kept trying to open the door through the glass door pane he had broken. So, he went outside and shot the kyd , right there on his back patio.
The man was about 40, owned the local Tru-Value hardware store, no priors, no arrests, clean as a whistle. However, the DA pressed charges, with the dead boy's famblee and the media all up his ass, and the man ended up getting 8 1/3-25 years for voluntary manslaughter because he wouldn't take a plea bargain and honestly thought he would be found NOT guilty. If he had taken the plea bargain then he would have not served more than a few months, if any, in jail. He ended up in a state prison for nearly nine years and his whole life, as well as his famblee's, was ruined. No one seemed to give a damn that the kid EASILY looked like a grown man at night, was hopped up on some sort of upper AND drunk, and no stranger to juvie hall. Of course the kyd's prior juvie convictions and arrests were inadmissable.
I think that if an intruder is on your property when they clearly should not be, then deadly force should NOT be against the law, EVEN IF the would be intruder is a "kyd". I am going to research the laws in the state where I recently moved and see how specific it is about killing intruders ON your property, rather than "in" it, just in case. That way I'll know whether to drag his lifeless ass inside before calling the police, after he will have NO DOUBT been shot if he tried to enter my residence. I'd rather be alive in jail then dead in hell, or wherever.