Justice Ketanji Brown Jackson continues to make her mark early in her Supreme Court tenure by calling out colleagues when she thinks they’re misguided. The latest evidence came Thursday in her lengthy, methodical dissent arguing that the 8-1 opinion against a union “risks erosion of the right to strike.”

The majority opinion by Justice Amy Coney Barrett in Glacier Northwest v. Teamsters lets a concrete delivery company’s lawsuit proceed against the Teamsters union. The company, based in Washington state, alleges that the union intentionally destroyed concrete when workers walked off the job in 2017 with wet concrete still in the trucks.

“The Union’s actions not only resulted in the destruction of all the concrete Glacier had prepared that day; they also posed a risk of foreseeable, aggravated, and imminent harm to Glacier’s trucks,” wrote Barrett, a Donald Trump appointee.

“Because the Union took affirmative steps to endanger Glacier’s property rather than reasonable precautions to mitigate that risk, the NLRA does not arguably protect its conduct,” she wrote, referring to the National Labor Relations Act. (In concurring opinions, Justices Clarence Thomas, Samuel Alito and Neil Gorsuch went even further against labor.)

Dissenting alone, Jackson said the court wrongly inserted itself into this stage of the ligation and, on top of that, wrongly analyzed the situation to the detriment of the right to strike. The Joe Biden appointee noted that the National Labor Relations Board’s general counsel has filed a complaint with the board claiming that the strike conduct here is protected. Jackson explained that, under long-standing precedent, a complaint pending before the board — which actually has expertise on the subject — means that courts have “no business delving into this particular labor dispute at this time.”

Yet instead of “modestly standing down,” the majority “eagerly inserts itself into this conflict, proceeding to opine on the propriety of the union’s strike activity based on the facts alleged in the employer’s state-court complaint,” Jackson wrote.

The justice reaffirmed the “general rule that labor strikes are protected even when the workers’ withdrawal of their labor inflicts economic harm on the employer.” She added that workers “are not indentured servants, bound to continue laboring until any planned work stoppage would be as painless as possible for their master.”

The court sent the case back to Washington state for further proceedings, which Jackson notes can still take advantage of her analysis. The prospect of Jackson’s view prevailing was apparently concerning enough to Alito, Gorsuch and Thomas that their concurrence dropped a footnote saying that going her way would make the case “a good candidate for a quick return trip here.”

For now, expect to see Jackson continuing to dissent in crucial cases as the term marches toward its unofficial end in late June. She’ll still be outnumbered, but she probably won’t be alone for long.

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