I am still horrified, wtbh. This is not how we train our police to respond to domestic violence calls. As a matter of fact, neither do the Troopers (you guys can watch all that now on TV!). I don't know where these two bozos came from, but don't' let two bad apples stop you from continuing a paper trail if need be. But now you know what can happen, so be prepared to corroborate your story with hard evidence, like video with time stamping.
You can get security cameras that are wireless, even at Best Buy which I am sure everyone has one in their community now:
Wireless Cameras: Wireless Security & Surveillance Cameras - Best Buy
They are relatively easy to install if you aren't afraid of pushing buttons.
Don't let this defeat you - instead let it teach you a lesson - not everyone is actually going to believe you without hard evidence.