I went to school in the UK and there was a rape near my university. They had a program where males can come down and "voluntarily" get a cheek swab to "assist"

I went to school in the UK and there was a rape near my university. They had a program where males can come down and "voluntarily" get a cheek swab to "assist" in the investigation. This is also the country that has the MI5 which is a stated domestic spy agency. I am completely against the NSA spying but if you are living in the UK you have less privacy and less rights in regards to search and seizure. The police can also stop you at any time and question you.