A federal lawsuit to give legal personhood to the Colorado River has ended.

An environmental group in Colorado, Deep Green Resistance, had sued that state and its governor on behalf of the river.

The idea was that the Colorado River, as a person, could sue over environmental damage and other threats to its health, especially if there wasn’t a human being who was directly suffering from a given threat and could serve as a plaintiff. If the personhood suit were successful, Deep Green Resistance argued, it would then represent the Colorado River.

The group’s lawyer, Jason Flores-Williams, walked away from the lawsuit this week. “Either American society and our law is ready for this expansion of rights or it isn’t,” he said. “And it appears like right now, at this point, it’s not.”

Flores-Williams said he had to protect his law practice for the future. The state of Colorado had threatened to sanction him under a court rule against frivolous arguments. Flores-Williams then filed a motion to dismiss the suit, and the federal judge granted it.

But while the effort to give the Colorado River legal rights was unsuccessful, Flores-Williams said the case raised the profile of what’s called the “rights of nature” doctrine.

“Before, if you talk about ‘rights of nature’ in the United States, people’d look at you and say ‘what are you talking about?,’” Flores-Williams said. “Now they know what you’re talking about. So in some ways we’ve created a framework possible for others to go forward.”