Thousands of National Health Service (NHS) patients have had their data accessed by the Home Office as part of a crackdown on illegal immigration. The data are made up of non-clinical information, which includes names, dates of birth and the individual’s last known address. An investigation by the Guardian revealed for the first time the extent and details of Home Office requests for information. Between September and October 20126, 2,224 such requests were made: in 1,659 cases the details were traced, in 516 there was no trace, and in 69 instances requests were turned down. The number of requests has risen threefold since 2014, as the Government has toughened its stance on illegal immigration. Data can be requested about people who have absconded from immigration control, escaped detention, exceeded their time in the UK, sought to obtain leave to remain by deception, or failed to comply with reporting restrictions. It should be noted that NHS Digital retains the right to refuse requests which it deems to be against the public interest.