The National Labor Relations Board said in a complaint filed Thursday that it is investigating Tesla (tsla) for unfair labor practices.
Workers and the United Auto Workers Union filed complaints with the federal agency in April that make an array of allegations, including that employees at its factory in Fremont, Calif. were interrogated over union activities. They claimed management tried to prevent them from discussing these along with worker safety concerns.
The NLRB has consolidated these into one complaint and has opened an investigation.
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An effort has been underway for years to unionize Tesla’s Fremont factory. The United Auto Workers has been working with employees since at least last year.
In response, Tesla said in a statement that the UAW has strayed from its original mission, used “every tool in its playbook” in its campaign against the company. Tesla’s complete statement is posted below.