Too fecking right.. Told mine never to speak to strangers and to walk away, this includes the police!
They were within there rights to ask your boy some basic questions, what do you people think they should have done ?, knocked his dads door before entering any sort of dialog ?.
Don't get me wrong i to think you should go down and sort it out but don't loose the moral high ground by making shit up about nightmares and bed wetting FFS.