The USA for example has a law which requires an alien to carry [immigration documents / ID](https://www.uscis.gov/ilink/docView/SLB/HTML/SLB/0-0-0-1/0-0-0-29/0-0-0-8289.html) on their person at all times. When flouted it is a misdemeanor and punishable by up to 30 days imprisonment. > Every alien, eighteen years of age and over, shall at all times carry > with him and have in his personal possession any certificate of alien > registration or alien registration receipt card issued to him pursuant > to subsection (d). Any alien who fails to comply with the provisions > of this subsection shall be guilty of a misdemeanor and shall upon > conviction for each offense be fined not to exceed $100 or be > imprisoned not more than thirty days, or both. Does such a law for aliens exist for the UK and does my credit/debit card with my name suffice as ID (not for driving, just for example if a ticket officer wants to check my ID on the metro) in the UK?