A federal judge ruled that Idaho’s law banning secret filming of animal abuse at agricultural facilities is unconstitutional, giving animal rights activists across the country hope that the decision will pave the way to overturn similar laws — known as “ag gag” laws — in other states.

U.S. Judge Court Judge B. Lynn Winmill found that the law violates the First Amendment.

“Audio and visual evidence is a uniquely persuasive means of conveying a message, and it can vindicate an undercover investigator or whistleblower who is otherwise disbelieved or ignored,” Winmill wrote in his 29-page ruling. “Prohibiting undercover investigators or whistleblowers from recording an agricultural facility’s operations inevitably suppresses a key type of speech because it limits the information that might later be published or broadcast.”

A coalition of animal activists, civil rights groups and media organizations sued the state more than a year ago, opposing the ag gag’ law. The coalition said the law curtailed freedom of speech and made gathering proof of animal abuse a crime with a harsher punishment than the penalty for animal cruelty.

According to the law, people caught surreptitiously filming agricultural operations face up to a year in jail and a $5,000 fine. By comparison, a first animal cruelty offense in Idaho is punishable by up to six months in jail and a fine of up to $5,000. A second offense within 10 years of the first conviction carries a penalty of up to nine months in jail and a fine up to $7,000.

The ruling is the first in the country to deem an anti-dairy spying law unconstitutional, said Mathew Liebman of the Animal Legal Defense Fund, one of the lead attorneys on the Idaho case.

The only other similar lawsuit is in Utah, but more are likely to come after Monday’s decision, he said. Currently, eight other states have passed some sort of law against such surreptitious filming, even though many more have been introduced in state legislatures.

Wisconsin Republicans have said they plan to introduce an ag gag law here, but have yet to do so. The proposal has met with heavy backlash from the public.

“This decision vindicates the public’s rights to know how animals are treated before they become meat,” Liebman said.

Idaho lawmakers approved the law in 2014 after the state’s $2.5 billion dairy industry complained that videos of cows being abused at a southern Idaho dairy filmed in 2012 unfairly hurt their business.

The Los Angeles-based animal rights group Mercy For Animals released the videos, which showed workers at Bettencourt Dairy beating, stomping and otherwise abusing cows in 2012.

“Idaho’s lawmakers should be ashamed of wasting precious time and valuable resources enacting unconstitutional laws that threaten animal welfare, food safety, workers’ rights, and the environment,” Nathan Runkle, president of Mercy For Animals, the animal rights group that released the 2012 footage, said in a statement.

Many lawmakers argued the law was needed to protect private property owners’ rights. However, Winmill countered that there are already state and federal laws on the books that protect private property against theft, fraud and trespass.

State Sen. Jim Patrick, R-Twin Falls, who first introduced the legislation, argued back in 2014 that “This is the way you combat your enemies.” During a legislative hearing, he compared undercover investigators to terrorists and called them “marauding” invaders who use ruthless tactics to submit their foes into submission.

Patrick told The Associated Press on Monday that he was disappointed in the ruling and was still considering options on how to best move forward.

Attorney General Lawrence Wasden’s office declined comment. Spokesman Todd Dvorak said the office was reviewing the ruling.