The more than 110,000 strong fighting group has been at the forefront of the fight against ISIS in Iraq.
Its role is critical but controversial with human rights groups, which allege the units have committed atrocities in the battlefield against the minority Sunni population.
The bill, officially passed Saturday, makes the units an independent entity of the Iraqi Armed Forces that answers directly to the Prime Minister. Under the new rules, the units will be overseen by the Popular Mobilization Unit Committees, or PMUC.
