A political operative has raised concerns about a Supreme Court justice whom he believes is President Donald Trump's chief enabler.

During an episode of Court of History, journalist and former senior Clinton White House adviser Sidney Blumenthal discussed the reasoning behind a recent article he wrote for The Guardian about Supreme Court Justice Brett Kavanaugh.

"When you look beneath the surface, and you see certain dissents and statements and opinions, you find that Kavanaugh is playing an instrumental key role on Trump's key issues," Blumenthal said. "And he's really the most politically attuned, the one who is acting most like a political operative, and the results are catastrophic."

Blumenthal said Kavanaugh has aligned himself with Trump's agenda on immigration, birthright citizenship and "damaging" tariffs. The remarks underscore how Supreme Court opinions can shape policy debates well beyond the courtroom, especially when cases touch on enforcement powers and executive authority.

He pointed to Kavanaugh's concurrence that allowed immigration agents to stop people based on factors including ethnic appearance, speaking Spanish and working certain jobs, which Kavanaugh described as "a relevant factor" and "common sense." Blumenthal said the tactics later became known as "Kavanaugh stops."

Blumenthal also cited Trump's appeal of a decision that blocked his tariffs. According to Blumenthal, the Supreme Court sided with a lower court decision that called Trump's claims "unconstitutional," but Kavanaugh said, "Well, not only is it not unconstitutional, let me suggest certain laws and other kinds of citations of tariffs that you could cite" to get around laws stopping Trump's tariffs.

"He was playing the staffer to Trump," Blumenthal said. "And then Trump attacked the majority on the court as fools and dogs. But then he said, 'Kavanaugh, I'm so proud of him.'"

Blumenthal then criticized what he called Kavanaugh's "masterpiece of errors, factual revisionism and sophistry" on birthright citizenship. He said the justice built his argument on speculation about what the framers of the 14th Amendment would have wanted, a method that has become a recurring point of contention in constitutional disputes over how much historical intent should guide modern legal interpretation.

"This is mind reading in a time machine about a non-existent legal category projected forward," Blumenthal said. "This is a fantastical fiction."