Read between the lines.

He didn't kill night one, so he has powers we don't know about.

Night two he tried to kill an investigator--I doubt his story for this one. He's much more likely to infiltrate and try and get information out of someone he thinks is mafia than to just off them.

His comments today make it clear that he considers this being forced to work with the town.

This quote is nice:

Quote Originally Posted by Pizza
Shame he trusted me for even one whole round.
And the fact is, if you wanted to "use" him there's no logical reason not to do it for 6+ days or so. Will people who don't want to lynch him today be up in arms to lynch him tomorrow? Of course not.

No you just think they wont try to kill him. I say give him a turn to prove he's helpful to the town if he's useful we keep him him if not we lynch him. Oh and it doesnt matter if he's nk immune as its still a wasted kill if they try.
Why would they try? Please. I don't "just think" I gave good reasons. He's likely to be nk immune or have acquired doc protection, and a likely lynch which helps the mafia. Additionally there are two scum teams and that always makes a bit of wifom about killing. You just believe for no good reason.