The case Collins v. Yellen, 2020, revolved around the constitutionality of the structure of the Federal Housing Finance Agency (FHFA). The plaintiffs, shareholders in Fannie Mae and Freddie Mac, argued that Congress violated separation-of-powers principles by placing restrictions on President's power to remove FHFA Director. They also challenged an agreement between FHFA and Treasury Department which allowed Treasury to receive nearly all future net worth of Fannie Mae and Freddie Mac as dividends - a move they claimed exceeded FHFA’s statutory authority as conservator. In June 2021, Supreme Court ruled that limitations on president's ability to fire agency director were unconstitutional but rejected shareholder claims about dividend payments. The court held that while such removal protections are common for multi-member agencies or independent commissions with built-in checks against abuse of power; it is not justified for single-director agencies like FHFA where there are no similar internal checks.

In the dissenting opinion for Collins v. Yellen, Justice Clarence Thomas argued that the majority's decision to allow shareholders of Fannie Mae and Freddie Mac to challenge a 2012 agreement between the Federal Housing Finance Agency (FHFA) and the Treasury Department was incorrect. He contended that because FHFA acted within its statutory authority as conservator in agreeing to amend its preferred stock purchase agreements with Treasury, no constitutional violation occurred. Furthermore, he disagreed with the majority's ruling on severability - removing an unconstitutional provision from a statute while leaving rest intact - arguing it should not be applied here due to lack of clear congressional intent. He also expressed concern about potential negative implications this ruling could have on future cases involving administrative agencies' structure and accountability.