What is the ruling on laundering black money and benefiting from it, and is it permissible to donate it to poor relatives if it is illicit?

This act is forbidden and among the great sins whose repercussions may continue after death, such as spending counterfeit currency or selling narcotics. Its sins remain جاری upon its perpetrator as long as its effect persists, as Al-Ghazali said. The money acquired from these forbidden acts must be returned to its owners if taken unjustly, or disposed of by giving it to the poor, the needy, and for public welfare.