Police cant just confiscate it.
They can request for it if there is the chance that it provides evidence of a serious offence. even then you can still decline.
this is copied and pasted.
Under the Police and Criminal Evidence Act (PACE) of 1984, under section 19 subclause 3, "The constable may seize anything which is on the premises if he has reasonable grounds for believing that it is evidence in relation to an offence which he is investigating, and that it is necessary to seize it in order to prevent the evidence being concealed, lost, altered or destroyed." It is worth pointing out that "premises" in this context refers to "any place", as per PACE s23.
In addition, constables have the power to use 'reasonable and necessary force', under section 117 of the Police and Criminal Evidence Act: "Where any provision of this Act confers a power on a constable (...) the officer may use reasonable force, if necessary, in the exercise of the power". In practice, that means that a police officer can use force to take the camera from you. If they would have to do that, they would probably also arrest you for Assaulting or Obstructing a Constable in the Execution of His Duty (section 51 of the Police Act 1964), or perverting the course of justice.
