The battle for control of the Higher Council of Judges and Prosecutors (HSYK), the body which appoints senior members of the judiciary, lies at the heart of a feud between Prime Minister Tayyip Erdogan and US-based cleric Fethullah Gulen.
Gulen, whose followers say they number in the millions, has built up quiet influence in the police and judiciary over decades. Erdogan blames him for unleashing a corruption investigation he sees as designed to unseat him.
The decision to approve the law came after a night of heated debate and a brawl that left one opposition member of parliament with a bloody nose. Local media reported that Ali Ihsan Kokturk, MP for the main opposition Republican People's Party (CHP), was hospitalized with a broken nose.