Less than three months after a massive employee protest, Google is facing a new outcry from workers for advancing a controversial legal argument as part of a labor lawsuit. As first reported by Bloomberg, Google lawyers have argued against a crucial precedent allowing employees to use company email and other infrastructure to circulate petitions, as part of an ongoing dispute before the National Labor Relations Board.

Google made the argument defending anti-harassment actions by management, and says the legal filing has been over-interpreted. “We’re not lobbying for changes to any rules,” the company said in a statement. “This was a legal defense that we included as one of many possible defenses in the response to a charge.”

But employee groups disagree, taking the filing as a direct attack on their right to organize. “Google is aiming to silence us at a time when our voices are more essential than ever,” the official Google Walkout group said in a statement. “If these protections are rolled back, Google will be complicit in limiting the rights of working people across the United States.”

In particular, organizers say Google is using anti-harassment measures as a pretense for rolling back labor protections. “Google is weaponizing this internal harassment to limit workers rights,” says Yana Calou, who works with organizers at Coworker.org. “It’s really broken a lot of trust on these issues.”

Established under the Obama administration, the rule forbids employers from retaliating against employees who use company email systems to organize walkouts, circulate petitions, or form a union. It’s a crucial protection for employee organizers within Google, who might otherwise be subject to retaliation in response to the November walkout and other actions. Many experts believe the Trump administration’s labor board might reverse that protection, and activists worry Google’s argument might give it a pretense to do so.

Google’s position in the case itself is sympathetic to many of the organizers’ broader demands. The plaintiff is anonymous, but argues his rights were infringed when the company disciplined him for internal comments dissenting from the company’s “very very left wing culture.” In particular, the comments dealt with “workplace diversity and social justice initiatives.” Google maintains that it has the right to discipline employees when comments amount to internal harassment, as it did in the Damore case last year.

Still, labor groups are worried that Google’s strategy for short-term victory could post a longer-term threat to organizers. Google won the Damore case without overturning any broader precedents, and organizers say it shouldn’t be necessary here either. “The Damore case established that talking about working conditions doesn’t give you the right to question your coworkers for immutable characteristics like race or gender,” Calou says. “They’re separate issues and the fact that Google would use that as a foil is really sad.”