Three current Amazon employees are under internal investigation after publicly advocating for Seattle to regulate data centers. The workers believe they are being unfairly targeted for expressing their political beliefs outside of work.

The employees have filed a complaint with Seattle’s Office for Civil Rights, accusing Amazon of attempting illegal retaliation against them. They argue that the company is trying both to silence collective action by workers and dodge public criticism through confidentiality agreements.

The affected workers say they were separately called into virtual meetings with an Amazon employee relations staffer last Wednesday, where they were told an investigation may take one to two weeks. The HR representatives directed them to use a speaker registration form that the employees don’t feel applies to their personal comments.

Speaking at city council meetings this month, the workers identified themselves as members of Amazon Employees for Climate Justice, a collective advocating for better handling of climate issues by tech companies. They claim no internal criticism aside from the HR meetings and received numerous messages of support from colleagues.

The employees took to the city lectern to speak on various regulations that Seattle is considering imposing on data centers, despite Amazon not having any current or proposed projects in the city.