perhaps saw the Serena murder and, knowing Chad had fought with her was doing what he could to frame him. He may not know who the actual murderer is but is suffering from guilt pangs now that Paige is dead and he knows that the police are on to the wrong guy because of him.
On a somewhat related subject what is wrong with Brian Datillo’s arm? Anything really or is that just another red herring to make us wonder how Lucas really hurt his arm, since his excuse was so lame, and could he be the killer? Although in retrospect if anyone had a million reasons to go over the edge it would be poor loser in love Lucas, LOL. I really wish they would do something positive as far as a storyline for him.