In a federal court case over Starbucks’s alleged anti-union retaliation, the coffee giant is deploying a maneuver that labor experts say could have a chilling effect on workers’ organizing efforts and potentially set a disastrous precedent — hijacking the proceedings to dig up information on employees and intensify retaliation as part of its battle to crush a labor uprising in its stores.

That includes the Buffalo location where employees launched the Starbucks Workers United organizing campaign that has now spread nationwide — and where the company fired six workers in alleged retaliation for organizing.

Federal labor regulators are suing Starbucks on behalf of the union and workers over its conduct, but last October, a Trump-appointed judge in Buffalo, New York, ruled that as a defendant in the case, Starbucks is allowed to use subpoena power to obtain employee communications — even though the company can then use those communications to identify union sympathizers within its workforce.