A politician does not have jurisdiction to tell the police to stop anyone from making a video of him at an open public meeting.
Just because the politician might be paranoid about the possibility of a video being filmed of him and that it may be used against him in the future does not give him the right to use the public police to prevent a video from being filmed at a public meeting. The police are there for the public and should actually be supporting the public during the making of a video- they should not hinder the process.
It is the same for any other public situation. Take, for example, a bad hair day. I could not prevent anybody from filming me and my hideous hair, let alone could I make the police stop anyone from filming me. Rather than forcing people not to film me, I should not give people any reason to film me. To accomplish this I could prepare myself appropriately by styling my hair in a more becoming way and, in the politician’s case, he could make his speeches, actions, and remarks more amiable and polite.
In conclusion, a politician does not have any right to order the police to stop someone from filming him at a public meeting or place, just as I cannot make the police stop anyone who wants to film me or my hair.