PM'd you Ska.
I have rolled out CCTV systems through massive places in the UK as part of my job (These days it is part of the computer systems known as IP CCTV) and whilst it is easy to capture these people (By webcam etc) staying legal and being able to use this evidence is extremely difficult in a court. You must ensure all your neighbours within the cameras field of vision consent to this as you are recording their property, ideally a signed piece of paper, as well as clear advertising on your house. In addition you must prove your timestamping is accurate (Sync'd to web time server etc) and that the footage is untampered with etc.
Or if you just want a face shot so you can kick his head in stuff it
