I don't think Mom or Dad would testify, I think he was face timing or whatever with the retarded girl (before you ask which one, you know which one, Mel). He didn't just sit up and she popped him, he had been loudly talking to a sped. Likely for a while, then he poked her(or something), then she popped him. That's my head cannon anyway.. but I guarantee Mom or Dad wasn't in his bedroom when it happened and wasn't a witness, it was someone online if not the retard.
ETA
@Soapmore he's been accused of molesting his "niece", Meg's child, but it was Sam that made the accusations so bucket of salt. He also didn't fall of the wagon til he left the Netherlands, he may have been stoned, but he wasn't sloppy drunk then.