A leading conservative U.S. Supreme Court advocate on Wednesday urged the justices to uphold the single-director independent design of the Consumer Financial Protection Bureau, arguing that Congress had authority to limit the power of the president to fire the agency’s leader.

The justices are set to hear arguments in the case Seila Law v. Consumer Financial Protection Bureau in March, and the dispute is widely viewed as a potential blockbuster in the constitutional law arena. The case is focused on a consumer regulatory agency long demonized by Republicans on Capitol Hill. The Supreme Court’s newest member, Justice Brett Kavanaugh, has assailed what he called the consumer bureau’s “massive, unchecked power.”