A lot has already been said, but I'll put in a couple of fresh observations:
1. Corrina has given Clark the only plausible reason (from his POV) not to turn himself in--Metropolis needs Superman and Lois is in danger from Lana. Clark needs those exact motivations to keep him from, as Martha put it, "doing what he thinks is right."
2. The witness saw Clark shoot Mayson. Does anyone else find it significant that Lana is dressed as Clark? If Lana, dressed in Clark's clothes, shot Mayson, it would be easy for someone else, say, looking through the curtains of Clark's front door or seeing the shooting from afar, to identify the shooter as Clark. Who else would you expect to see in Clark's apartment wearing Clark's clothes?
Looking forward to the next part.
