I've just had a conversation with a company who are a "Security Systems and Alarms Inspection Board accredited intruder alarm system installer", who told me that their CCTV cameras and network video recorder devices cannot share our IT IP network, even with logical VLAN separation, because it would make images gathered likely to be inadmissible in court because they cannot be shown to be "evidence compliant". Instead they prefer to have their own IP network dedicated to CCTV only.
The person with whom I spoke couldn't cite a specific regulation that dictated this. In the past I have worked with other installers where the cameras where in a VLAN of the main IP network, and the network video recorder was virtualised on one of the IT servers, again with logical separation. I am now wondering if these are somehow non-compliant.
If someone can help me understand the accurate legislation here, or perhaps cite some design guidelines that would help in court, that would be great. Thank you.