Police can check neighboring cctv to see if they invade your privacy.
"...,,For example, if you have a camera which is pointed directly at another person’s property or it’s suspected that it can capture part or all of a neighbour’s property, they might have a case to take action against you under legislation covered by the Human Rights Act. They might have sufficient grounds to say that they have had their privacy violated, that your CCTV system is tantamount to harassment and even voyeurism.
In such cases, they can get the police involved if you're not able to come to some agreement with regards to what the camera(s) can capture and to make modifications to the installation, if necessary...."
http://www.problemneighbours.co.uk/cctv-privacy-and-the-law.html