Amazon workers who have criticized their employer for its response to climate change released a video about their campaign on Monday, defying a corporate policy requiring them to request permission before publicly speaking about the issue.
The video was released one day after 357 Amazon employees contributed to a Medium post about their belief that Amazon is contributing to the climate crisis, isn’t doing enough to stop it, and is attempting to stifle their right to speak out about it. The employees added full names and job titles to the post.
“The science on climate change is clear. It is unconscionable for Amazon to continue helping the oil and gas industry extract fossil fuels while trying to silence employees who speak out,” said Amelia Graham-McCann, a senior business analyst and one of the Amazon employees who spoke out.
Earlier this month, some employees told Fortune that Amazon warned them that they would be terminated if they continued to speak out without first getting approval. An Amazon spokesperson said that process was communicated to workers last year, however the employees said it’s time consuming and involves too much red tape for such an urgent topic.
In the video, Amazon employees show their faces and hold signs saying they won’t be silenced. A narrator alleges that the employees are speaking out after the company disciplined some of them for giving a quote to the Washington Post last year that Amazon should not help oil and gas companies find and extract natural resources.
“Corporations can not own conversations that affect our very existence,” said the narrator of the video.
An Amazon spokesperson told Fortune that the company is committed to reducing the affects of climate change and said it has clearly stated its position online.
“While all employees are welcome to engage constructively with any of the many teams inside Amazon that work on sustainability and other topics, we do enforce our external communications policy and will not allow employees to publicly disparage or misrepresent the company or the hard work of their colleagues who are developing solutions to these hard problems,” the company said in a statement.
An Amazon spokesperson also pointed to several of the company’s efforts, including a commitment to net zero carbon emissions by 2040. To help achieve this goal, Amazon has ordered 100,000 electric delivery vehicles and plans to use 100% renewable energy by 2030, the spokesperson said.
A representative for the Amazon workers said the group hasn’t yet received any communication from Amazon human resources or legal teams about whether workers would be disciplined or terminated for speaking out. Employees can speak about their personal work experiences at Amazon, as long as they make it clear they aren’t speaking on behalf of Amazon, according to the company.
Amazon requires external communication about its business, products, services, technology, and customers to be approved in advance before an Amazon employee speaks in a public forum. This includes social media posts.
On Monday, the 357 employees received a high-profile vote of support from Democratic presidential candidate Sen. Bernie Sanders, a frequent critic of large corporations, who tweeted his solidarity.
“I stand with these Amazon employees who are courageously speaking out. They are telling Jeff Bezos to end his hypocrisy: You cannot call your corporation a ‘leader’ on climate change while partnering with ExxonMobil and BP to extract more fossil fuels,” Sanders wrote.
On Monday, the Amazon Workers For Climate Justice Twitter account continued to share quotes from employees about why they want to see Amazon do more. For Mark Hiew, a senior marketing manager for Amazon in Seattle, the urgency of the topic is hitting especially close to home.
“As someone who grew up in Australia, the devastating reality of our climate crisis has become all too clear as I watch my homeland burn and millions of native animals being killed. This is not the time for silencing voices,” he said. “We need policies that welcome more open discourse, more problem-solving, and more urgent and concerted action about climate change and its causes.”
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