Sarah Wynn-Williams, the former Meta executive and author of a bestselling memoir about the tech company, appeared before the Senate Judiciary Committee Wednesday, blasting the corporation for its business dealings with China, the Associated Press reports.

Wynn-Williams’ Careless People: A Cautionary Tale of Power, Greed, and Lost Idealism was published last month by Flatiron. In the book, Wynn-Williams, who served as Meta’s director of global public policy for six years, accuses the company of cozying up to the Chinese Communist Party and its leader, President Xi Jinping.

A critic for Kirkus wrote of the memoir, “Book: thumbs-up. Subject: frown emoji.” Last month, an arbitrator temporarily blocked Wynn-Williams from promoting the book.

Wynn-Williams told the Senate Judiciary Committee, “We are engaged in a high-stakes AI arms race against China. And during my time at Meta, company executives lied about what they were doing with the Chinese Communist Party to employees, shareholders, Congress, and the American public.”

The Washington Post reports that Wynn-Williams took aim at Meta’s co-founder and CEO, Mark Zuckerberg.

“If he is such a fan of freedom [of] speech, why is he trying to silence me?” she said. “The other thing is that this is a man who wears many different costumes. When I was there, he wanted the president of China to name his first child. He was learning Mandarin. He was censoring to his heart’s content.”

Michael Schaub is a contributing writer.