The police officer didn't witness the crime. They're making that Judgement based on evidence provided by a third party.

If my house were broken into, and I managed to capture video of the incident, I can't just hand that to the police and call it a day. The accused has a constitutionally protected right to face me in court, not just the video or the officer I gave the video to, so that their defense can interrogate it fully. What if there is additional context that undermines the narrative presented by this single piece of evidence? If I know the accused and had a reason to see them convicted (such as getting a kickback from any fine they pay), now my clear evidence becomes a little more suspect. Now there's a very clear motive for me to skew, misinterpret, or completely fabricate the video.

That's what OP is referring to. If a company is going to install cameras and claim their cameras caught me doing something I shouldn't have, I have a right to ask that company for more details regarding their claim. Ideally in a public court, with a representative of the company under oath.