the surveillance footage is evidence, not an accuser.
in your murder example, you would still need to be arrested by a physical person in a police uniform, you would have some interaction with an agent of the state.
when you get a ticket in the mail, who is your accuser? Whose name is on the ticket? what is their badge number? how do i lodge a complaint against this officer? Who is expected to show up in court to prosecute this case?
