Can anyone tell me the legal definition of a POLICE Witness?
If you are a material witness to a criminal act, you can be compelled to attend court under summons, but nothing else. As long as you do not attempt to pervert the course of justice or withhold information of a criminal act, you are entitled to be as helpful or unhelpful as you wish. You may or may not have a civic obligation or duty to assist the police, that somewhat depends on your viewpoint – but such duty or obligation is little more than a moral obligation/duty – it is not legally compellable, it has no legal meaning or force. There is no such thing in the UK as a ‘police witness’ – there is just ‘a witness’ who is compellable by either prosecution or defence – or sometimes both. As all lawyers know: “there is no property in a witness” meaning that neither side ‘owns’ a witness.
