Have to disagree with them. It's a recording of the police doing their job. The subject matter of the video takes place in full view of the public so there's no reason to later make it private. In many ways, it is similar to police reports - a recording of some interaction between the police and the public - and those are public record.
Additionally, the public good is advanced by making the videos public record. The public has every right to view the way their police engage with the public (as noted earlier - these engagements happen in the open in the first place) and, as public servants, I can't think of a compelling police need for keeping them private.