The difference between first and second degree murder is the level of intent. First degree murder is premeditated murder, murder planned in advance.

I don't know all the legal details of New York's murder statutes, but I have a hard time understanding how you can kill somebody over the course of a month while torturing them, and not have that be premeditated. How does that work?

By the way, I've been able to access some of the gruesome details, and it doesn't seem to me that the murderers could possibly have had any intent for Sam to remain alive. It boggles the mind!