They are people who arrived in the UK after the second world war from Caribbean countries at the invitation of the British government. The first group arrived on the ship MV Empire Windrush in June 1948. An estimated 50,000 people face the risk of deportation if they never formalised their residency status and do not have the required documentation to prove it. It stems from a policy, set out by Theresa May when she was home secretary, to make the UK 'a really hostile environment for illegal immigrants'. It requires employers, NHS staff, private landlords and other bodies to demand evidence of people’s citizenship or immigration status.
Source: The Guardian April 18, 2018 13:15 UTC