Opinion | Black Lives Matter, Now at Home Depot

If you’re finally getting used to endless protests on every college campus, get ready to deal with them on your weekend shopping trips. A federal ruling this week could block bosses from setting ground rules for political agitation in their workplaces—even for causes that have nothing to do with work.

The National Labor Relations Board (NLRB) on Wednesday ordered Home Depot to rehire a man with back pay, after the store sidelined him for breaking its dress code in early 2021. Antonio Morales had written “BLM” on his work apron in tribute to the Black Lives Matter movement. That clashed with the company’s policy against “displaying causes or political messages unrelated to workplace matters.”

Mr. Morales had previously joined a few colleagues to hang posters commemorating black history month, and he was upset when they were torn down. He didn’t witness the act and doesn’t claim that managers were behind it, but he decided the removal was “racist.” He also demanded a “storewide conversation” to make sure “people of color feel safe at this store,” according to an email he sent to a manager. He resigned days later after a meeting in which he pledged to keep up his activism.

In its 3-1 decision, the NLRB ruled that Mr. Morales’s actions are protected by labor law, which lets employees organize on the job. The 1935 National Labor Relations Act guarantees that workers can take public positions on workplace conditions or joining a union, whether or not their bosses want it. The agency’s three Democratic appointees extended that protection to Mr. Morales’s BLM letters.

The ruling widens the scope of protected political action at work, with no obvious limiting principle. The board says the BLM sign is a “logical outgrowth” of Mr. Morales’s organizing for racial justice with fellow workers, making it a symbol of his labor advocacy.

By that standard, workers almost anywhere could adorn themselves in political slogans, against company policy, as long as they enlist a few colleagues in the cause. McDonald’s fry cooks might swap their aprons for National Rifle Association shirts, claiming the Golden Arches made them feel unsafe by forbidding open carry. They wouldn’t even have to prove they were discriminated against.

The Home Depot ruling shreds decades of precedent that draws a clear line between labor advocacy and political agitation that could affect an employer’s image. Labor law has never before stopped employers from regulating speech with no clear connection to workplace conditions.

The NLRB also overruled its own administrative law judge, who backed the retailer in 2022. Judge Paul Bogas wrote that “a message about unjustified killings of black men” is “not directly relevant to the terms, conditions, or lot of Home Depot’s employees as employees.” In December a different NLRB judge said Whole Foods didn’t violate labor law by banning BLM-labeled gear.

The NLRB ruling is one more effort by Biden appointees to do favors for progressive groups, never mind the law. Home Depot has a strong case if it challenges the ruling in federal court.