Well, as Alex pointed out, it's sorta metagame knowledge that I will be greatly overlooked.
Out of curiosity, are you sure there's nothing more than a strong hunch that had you thinking I was scum? Did you know there was only one scum, or did you think I was scum acting with someone else?
I confess to being unable to see the point of a Miller role without some sort of investigative role. The only thing I can see that doing is being a blatantly anti-town plant, such that at claim time the poor individual is forced to claim what he's been given and claim accurately in case there IS a cop role he's unaware of.