Why not go knock on the neighbour's door and ask them what their difficulty is/isn't? Calling the police before speaking with you is, at least in my view, pretty lame. I not suggesting a fight- but if they plan to call the police over everything they don't like- might be good to know this and also make them aware you aren't one of their kind who will hide behind curtains and call police - you will come knocking on their door if you have a problem, or, barring that- ask them if the police should be the first people you do call if you find one of their kids meandering around your property or see them driving their car a bit off-kilter down the road (could be drinking and driving don't you know). Some people have a real tough time with the idea of "what goes around comes around" no matter how perfect they might believe themselves to be.