WASHINGTON — The undercover investigator who secretly videotaped alleged animal abuses at a meat processing plant in California’s San Joaquin Valley would have been a criminal for doing the same thing in Utah, potentially subject to a year in jail.

Since March, it’s been a misdemeanor in Utah to videotape an agricultural operation without the owner’s approval.

Nor is Utah alone in trying to shield farms from private investigators and prying media. Kansas, Iowa and North Dakota have all tightened access.

Prompted by the agriculture industry, states are debating, and in some cases adopting, so-called “ag-gag” laws that add to the legal and ethical restraints inherent in undercover work “Undercover investigations are a very tricky business,” noted Jonathan Lovvorn, senior vice president of the Humane Society of the United States. “They are not something for amateurs to attempt. The rules are different in every jurisdiction.”

The balancing act is particularly delicate because animal rights groups have a big incentive to try out undercover investigations that, when successful, can mobilize the press, the public and politicians alike.

The Washington-based group Compassion Over Killing, for instance, spurred action by the U.S. Department of Agriculture after it released videotape taken at the Central Valley Meat Co. in Hanford, Calif. The group’s investigator worked at the facility for two weeks in June and July.

The California meat processor, which employs about 500 workers, was forced to suspend operations Monday. On a broader front, a Humane Society undercover investigation several years ago revealed horrific conditions at two meatpacking plants in Southern California. The investigator’s video showed non-ambulatory cattle being kicked, shocked with electricity and dragged with chains. The public outcry led to a 2008 state law prohibiting the slaughter of downed livestock.

In January, the U.S. Supreme Court struck down the California law’s provisions covering swine because they infringed on federal authority. The court ruling did not speak to the undercover investigation that prompted the law.

“We have done undercover investigations into animal cruelty for decades,” Lovvorn said. “We provide extensive training for our folks.”

Cheryl Leahy, the general counsel of Compassion Over Killing, declined to provide further details about the undercover investigator who worked at Central Valley Meat or the rules that guided the investigator’s behavior.

But the work is getting riskier.

In Kansas, it’s illegal to “enter an animal facility to take pictures” without the owner’s consent. It’s also against the law in North Dakota, where violators can be sentenced to 30 days in jail.

While a new law in Iowa law doesn’t cover videotaping, legislators made it a “serious misdemeanor” to obtain access to an agricultural production facility under “false pretenses.” This would potentially cover an investigator misleadingly seeking employment, which is how Compassion Over Killing obtained its video about Central Valley Meat Co. The organization behind the sham employee would also be at risk because Iowa legislators extended the law to cover anyone who “aids and abets” those who deceive a farm employer.

“People are trying to get into these places, saying they’re a plumber or they’re this or that . . . with no intention of that whatsoever,” Iowa state Sen. Joe Seng, a Democrat and a veterinarian, said during the February debate, according to news accounts. “They’re trying to bring down this business.”

Civil liability, or at least some long-running court hassles, can likewise await the undercover animal rights investigator.

Ottavio Gesmundo was a Las Vegas dancer at the Stardust Hotel’s “Lido” floor show in the late 1980s when he became upset over the treatment of show animals by trainer Bobby Berosini. Gesmundo covertly filmed Berosini “shaking, punching and beating” orangutans, according to subsequent court records. People for the Ethical Treatment of Animals made the film public, and the Stardust canceled Berosini’s show.

Berosini sued Gesmundo and PETA for defamation and invasion of privacy, and a Nevada jury awarded the animal trainer $4.2 million. This was later overturned by the Nevada Supreme Court, with reasoning that might apply to future undercover cases.

“Even if Berosini had expected complete seclusion from prying eyes and ears, Gesmundo’s camera was not ‘highly offensive to a reasonable person’ because of the nonintrusive nature of the taping process, the context in which the taping took place, and Gesmundo’s well-intentioned, and in the eyes of some, at least, laudable motive,” Justice Charles Springer wrote for the Nevada court.

Trespass is another potential vulnerability for investigators, as two ABC reporters learned in the 1990s when they went undercover to investigate the Food Lion supermarket chain. A jury awarded Food Lion $5.5 million for trespass and fraud. Though an appeals court later lowered this to $2, judges agreed the undercover investigators had trespassed on Food Lion’s property.

“They went into areas of the stores that were not open to the public and secretly videotaped, an act that was directly adverse to the interests of their second employer, Food Lion,” the 4th U.S. Circuit Court of Appeals reasoned.

The reporters, the court said, “breached the duty of loyalty.”