[1] McFadden clerked for Judge Steven Colloton of the United States Court of Appeals for the Eighth Circuit from 2006 to 2007.

[10] In April 2019, the U.S. House of Representatives requested that McFadden issue a preliminary injunction against the Trump administration's plan to divert about $6 billion from military construction and counter-drug appropriations to build a wall along the U.S.–Mexico border, arguing that the Trump administration's action violated the Constitution's Appropriations Clause.

Citing the McGahn case, the appellate court held that a single chamber of Congress has "standing to pursue litigation against the Executive for injury to its legislative rights"; the court also criticized the Trump administration's argument that "the Executive Branch can freely spend Treasury funds as it wishes unless and until a veto-proof majority of both houses of Congress forbids it" as a position that "turns the constitutional order upside down.

McFadden ruled that Trump was "wrong on the law" and that Congress is due "great deference" in its inquiries, allowing the tax returns to be released to the Committee.

Fusion GPS, the research firm which had commissioned the dossier and to whom the subpoenas have been issued, requested that McFadden step down from the case for potential conflict of interest.

McFadden ruled "The President's connection with me and his interest in this case are simply too tenuous to cause a reasonable observer to question my impartiality."

[20][21][22] Subsequent to Cudd's filing of her travel request, she was indicted on five federal counts, including one felony, relating to her alleged activities during the January 6, 2021, storming of the United States Capitol.

"The US Attorney's Office would have more credibility if it was even-handed in its concern about riots and mobs in the city," said McFadden during sentencing for one of the Capitol rioters.

In his opinion, Judge McFadden described the minors involved in the case as behaving in "classic teenager fashion" by seeking to be vaccinated notwithstanding their parents' disapproval.