Assalamualaikum. Please advise: a close family member is trying to use deception to gain a residence visa and government housing in the UK. There is some truth in the application mixed with falsehood in order to try to obtain the visa. Do I have to inform the authorities about the deception even indirectly? Bearing in mind this would reveal the person’s sin and possibly incur harm on the person involved as well as myself and children. May Allah reward you with good.

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad, sallallaahu 'alayhi wa sallam, is His slave and Messenger.

What you must do is advise him and remind him of the prohibition of cheating and lying, and that these are not among the morals (characteristics) of the Muslims.

As for reporting him to the authorities, then do not report him because this will result in harming him.

Allah knows best.