The ILR of a person can be revoked if that person:
1. Is liable for deportation: The UK Secretary of State may find a person liable to deportation if they decide that the individual is conducive to the public good.
2. Has obtained leave or entered the UK by deception: A person’s indefinite leave to remain or indefinite leave to enter can be revoked if the Secretary of State believes that the person has used deception to obtain their stay or entered the UK by ‘making false representations or submitting false documents (whether or not material to the application), or failing to disclose material facts’.
3. Ceases their refugee status as a result of their actions: This is applicable in instances where a person is ‘voluntarily establishing themselves in a country in respect of which they were a refugee’, ‘voluntarily re-acquiring a lost nationality’, ‘acquiring the nationality of a country other than the United Kingdom and availing himself of its protection’, or is ‘voluntarily establishing himself in a country in respect of which he was a refugee’.
So if they deceived HO to gain their ILR, their ILRs can be revoked.
More:
https://www.gov.uk/government/uploads/s ... ctober.pdf
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