I know a slap on the hand, and have received a few in my day - got no points last time in traffic court
When you get that ringing slap, you're gonna have a hard time convincing me they got hand. 99% of the time it was more than a high five. You still have to decide if you have a call, but I think the resounding slap no-calls annoy me more than any others. That there was contact!