Former NLRB member Gwynne Wilcox has sued over her unprecedented removal from the board by President Donald Trump, in a case that could test the limits of presidential authority over independent agencies.

Gwynne Wilcox alleged that President Trump exceeded his authority and broke with nine decades of precedent in ousting her from the agency that oversees unions and workers’ rights.

The former head of the National Labor Relations Board (NLRB), a US labor watchdog agency, is suing President Donald Trump over her termination as an NLRB board member after the 47th President suddenly removed her from her position last week.