Is it permissible to donate money taken as a bribe, especially if returning it is impossible, and is it permissible to give it to a needy brother?

Whoever takes a bribe must repent and feel remorse. If the bribe was paid to achieve something unlawful and the briber succeeded, then it should not be returned to him. The recipient of the bribe is not permitted to keep it; rather, he must give it as charity to the poor. However, if the bribe was paid to achieve something rightful, then the recipient of the bribe must return it to the payer. If that is not possible, he should give it as charity, and it is permissible to give it to a poor relative.