Well, since "we're all cops here":
I'm going to propose that we split into three groups, of three, three, and four players.
One group should investigate Daveshack, one investigate Zack, and one investigate me.
We'll compare results then. I suggest we split into three groups so that the scum don't rob us of too many investigations through their Night Kill.
I assume this strategy is acceptable for this particular game; if not, PM me and I'll delete this.
It's quite acceptable, though I'm rather suspiscious of you asking to be investigated. Vote: JoanK