Some random thoughts- an identity card is a (plasticized) piece of paper. so was the (fake) drivers license an illegal immigrant used when he stole my son's identity, rented 3 luxury cars which subsequently disappeared, got son's mail redirected (he only accessed the gas bill, which the bu**er didn't pay) and a few other things. He got caught as his skin colour wasn't the same as son's, deported to his homeland and was probably back in Canada before the ink was dry on the 'export certificate'.
I'm 'white', quite familiar with the UK, and can still say "Oh aye" and "yuwha' " with a decent Yorkshire accent, so could probably avoid detection and seizure if I returned to the UK for a long, illegal, stay.
I'm old, bald, and so don't get the "outta the car, kid, licence, ownership & insurance' - now its "good evening sir, routine check, please continue".
I tend to agree with F3's first post, but he has more faith in the "charter of rights and freedoms" and its provisions than I do.
Perhaps the answer is to tattoo an identity number on every legal resident's wrist- as a teaching co-worker once suggested for student ID numbers (he had been in the Hitler youth). We weren't sure if he was joking.....