'it depends' - no one can give you a straight answer without seeing the context but either way, data protection rules will appy.
Crime prevention also isn't a catch all, in the context of your home CCTV, it's reasonble for you to cover your own property for crime prevention purposes but the road isnt your property. It may be reasonble to cover some of the public area but it should really be incidential and not the main focus of the camera.
See this post as an example of how not to do it (cam 1 specifically), personally I can't see how this could ever be considered 'reasonable' and therefore probably breaches data protection rules as you have no legitmate purpose to record the information in frame.
https://forums.overclockers.co.uk/threads/spec-me-a-cctv-system.18568132/post-25701779
The council or government on the otherhand are responsible for public order and law enforcement so that crime prevention justification is MUCH stronger.