A Google employee who helped lead protests over the company’s work for the military, its handling of AI ethics, and its sexual harassment policies has left the organization.

Meredith Whittaker was a program manager at Google, founder of the company’s Open Research Group, and co-founder of the NYU-affiliated AI Now Institute, which focuses on ethical questions involving artificial intelligence. The news was first reported by Bloomberg, and Google confirmed the departure to The Verge but refused to comment further.

In a blog post, Whittaker said: “The reasons I’m leaving aren’t a mystery. I’m committed to the AI Now Institute, to my AI ethics work, and to organizing for an accountable tech industry — and it’s clear Google isn’t a place where I can continue this work.”

Whittaker was a prominent voice for change at Google. When it was revealed that the company was building AI tools for military drones, she spoke out against the work, with fellow Googlers praising her “ethical leadership.” She also criticized the company’s decision to hire Heritage Foundation president Kay Cole James to sit on an external AI ethics board, which the company shut down following protests a week after its launch.

Along with fellow employee Claire Stapleton, Whittaker also helped lead last year’s “Google Walkout for Change,” in which 20,000 employees participated in a mass walkout to protest the company’s handling of sexual harassment allegations.

Protests against Google policies have led to real change

In each case, the protests Whittaker was involved with led to change at the company. In response to criticisms of its work with the Pentagon, Google pledged not to develop AI weapons. And after the fallout from the walkout cleared, Google ended its practice of forced arbitration for sexual harassment and assault cases, which requires employees to waive their legal rights.

Following these protests, Whittaker and Stapleton said they faced internal retaliation for their actions. Whittaker said she was told her job would “be changed dramatically” and that she would have to stop her work with the AI Now Institute. Stapleton later wrote that she had been “branded ... with a kind of scarlet letter that makes it difficult to do my job” and left the company earlier this year. “If I stayed, I didn’t just worry that there’d be more public flogging, shunning, and stress, I expected it,” she wrote.

In response to Stapleton’s departure, Whittaker tweeted in April: “Google’s retaliation isn’t about me, or [Claire Stapleton]. It’s about silencing dissent & making us afraid to speak honestly about tech & power. NOT OK. Now more than ever, it’s time to speak up.”

In her blog post, Whittaker said that Google is gaining “significant and largely unchecked power to impact our world” through technology like AI, and that deciding how this power is used “is one of the most urgent social and political (and yes, technical) questions of our time. And we have a lot of work to do.”

Update Tuesday July 16, 9:00AM ET: Updated with confirmation from Google.

Update Tuesday July 16, 12:40PM ET: Updated with comment from Whittaker’s blog post.