A Speedy Assumption

(I am chatting with my neighbor, and the topic has turned to speeding.)

Me: “My brother-in-law has a ‘Police Interceptor’ sticker on his car, so highway patrol knows not to pull him over. Though when he told us about it, someone also commented that it would be hard to even see the sticker at that speed.”

Neighbor: “Can’t you get in trouble for having one of those if you’re not a cop?”

Me: “He IS a cop.”

(I’m not entirely sure who’s the stupid one here; him for not making that leap of logic, or me for assuming he would.)