It helps me to see it from the other persons perspective in situations like this. 99% of the world doesn't have any idea what stuttering entails. It sucks, but he's just doing his job with someone he deems as suspicious. As my grandmother use to tell me: "at least you weren't born without feet". It's not "fair" but life is not and should not be fair. We could all have far worse problems to be born with. I know this doesn't help too much, but hopefully understanding the situation from his perspective can at least give you some peace. Good luck!