Is it permissible for him to accept membership in a Housing Society, which will enable him to get a flat for a cheap price?
Question

                My friend works in a Law Enforcing Agency. He once helped a Housing Society to rescue lands from illegal occupants. Recently that housing society is growing good.I a governing body meeting, they have decided to offer paid membership to about 50 persons from different ranks and files of the society who contributed in their Housing Society. This membership will allow a member to get a flat in that housing like the other members (on reduced payment). Will it be legal for my friend to accept that membership and eventually be owner of flat at cheaper price? or it will be considered as bribe?
Praise be to Allah.So long as your 
    friend is working for the government in law enforcement, which has some kind 
    of authority in this case, then he does not have the right to take any 
    reward, gift or payment for doing the job he is supposed to do and for which 
    he takes a salary from the state, because he is doing that on the basis of 
    trust that has been placed in him. 
Al-Bukhaari (6636) 
    and Muslim (1832) narrated from Abu Humayd as-Saa‘idi that the Messenger of 
    Allah (blessings and peace of Allah be upon him) appointed a worker. The 
    worker came to him when he had finished his work and said: O Messenger of 
    Allah, this is for you, and this was given to me as a gift. He said to him: 
    “Why don’t you sit in the house of your father and mother and see if you are 
    given any gifts or not?” Then the Messenger of Allah (blessings and peace of 
    Allah be upon him) stood up in the afternoon, after the prayer, and recited 
    the Shahaadah and praised Allah as He deserves to be praised, then he said: 
    “To proceed: what is the matter with a worker whom we appoint, then he comes 
    to us and says, This is yours and this was given to me as a gift. Why 
    doesn’t he sit in the house of his father and mother and see if he is given 
    any gifts or not? By the One in the Whose hand is the soul of Muhammad, no 
    one among you takes anything of it (unlawfully), but he will bring it on the 
    Day of Resurrection, carrying it on his shoulders: if it is a camel he will 
    bring it groaning, if it is a cow he will bring it lowing, and if it is a 
    sheep he will bring it bleating. I have indeed conveyed the message.” 
And Allah knows best.