A group of Texas cattle ranchers sued Oprah Winfrey for more than $12 million in 1996. They claimed that one of her shows, called “Dangerous Food,” that featured experts on mad cow disease and in which she said she would not eat another hamburger, was an attack on their business.

The ranchers did not really have a legal leg to stand on. But at the time, Texas did not have an anti-SLAPP law on the books so Winfrey had to fight the frivolous lawsuit in court for six weeks before a jury ruled in her favor.

Strategic Lawsuits Against Public Participation, known as SLAPP suits for short, are a type of lawsuit intended to silence or punish people who speak out on matters of public interest. They often attack protected free speech and have mostly been used by powerful and wealthy interests to harass.

The suits are usually not built to win in court, but rather to leverage the deep pockets of those filing the suits to bully less wealthy groups and individuals and force them to divert their time and resources to defending themselves in court. This is a tactic increasingly used by the fossil fuel industry and other corporate polluters to suffocate environmental activism and advocacy.

Winfrey obviously had the resources to fight back in that 1996 suit. Many targets of SLAPP suits are not so lucky.

Right now, Energy Transfer, the corporate behemoth behind the Dakota Access Pipeline (DAPL), is suing the organization Greenpeace for more than $300 million in damages in a SLAPP suit. Energy Transfer alleges Greenpeace orchestrated the massive protest movement against the pipeline, defamed the company, and cost them hundreds of millions of dollars.

In doing so, Energy Transfer fails to acknowledge that the movement to stop this pipeline was led by the Standing Rock Sioux Tribe, who simply wanted to protect their water supply, sacred sites, and cultural resources. Tribal leaders attracted the support of hundreds of organizations and thousands of activists, who promoted their efforts, joined the Tribe in North Dakota to protest, and signed letters in solidarity with their opposition to the pipeline.

Energy Transfer’s suit is built on the assumption that Indigenous peoples did not have the authority, agency, or wherewithal to organize the anti-DAPL movement. In that way, the SLAPP suit is a slap in the face to those Indigenous activist leaders.

Greenpeace’s role in the protests was fairly limited. They joined sign-on letters, had a small handful of organizers in North Dakota who joined the effort, and shared information from allies and the news on social media.

That is according to Greenpeace’s Chief Program Officer Tefere Gebre. Tefere and I go back a long way as brothers in the movement for working people. He says, “At the end of the day, it’s not just Greenpeace we worry about. We believe this is going to be a blueprint for corporate America to go after whoever they want and scare their opposition out of existence.”

That is 100% correct. This SLAPP suit is not just about tying up Greenpeace in court to hamper the organization’s work. Energy Transfer and their legal team are trying to sue Greenpeace out of existence.

Gebre says, “We don’t want people to just say ‘poor Greenpeace,’ we want people to speak up and actually stop this from happening. We’re not asking for sympathy, we’re asking for solidarity.”

The writer is the executive director of the Sierra Club and a professor of practice at the University of Pennsylvania.