A person is allowed to protect their property using CCTV systems, but there are some rules that must be adhered to in order to ensure that they are complying with the law. They need to be installed and used in such a way that they protect the privacy of others. So for example, you could not have a CCTV system that is pointing over in to a neighbour’s garden.
If you want to put a camera up that may record footage of your neighbour’s property and / or a public pavement / footpath then you need to try and limit this, possibly by adding privacy filters. Privacy filters can often be added through the CCTV software to block out areas that need not be recording or you may put something around your camera to ensure that these areas are physically out of sight.
Be sure to speak to your neighbours to tell them that you are putting up a CCTV system and let them know if it may record anything on their property. Also put up signs to say that CCTV is being used.
You should also delete unnecessary footage as soon as you can, so you are only keeping what is relative. You may have a system that can automatically record over older recordings after a certain time.