You see it all the time in mystery novels - 'Someone overly suspicious'. It can be a trap depending on how familiar you are with the genre, or read a lot of them in general. A first time reader would say that they're clearly guilty of whatever they're suspected of, because they haven't had enough experience to see other tricks in other stories.

But an experienced reader could potentially overthink it, and then go 'he's too suspicious, there's no way it's him.'

...Of course, that's just for mystery novels. But...We've got a lot of people experienced in investigation, right?