A wave of laws that target animal welfare activists who take undercover videos at factory farms has been criticized for chilling free speech and allowing cruelty to continue in secret. But it's not only animal well-being at issue. So is public health.

Some food safety experts say these so-called ag-gag laws will cloak disease-spreading industry practices, such as processing ill cattle and housing poultry in filthy conditions, in secrecy, raising risks of food contamination.

"The ag-gag laws are touted as preventing animal activists from getting access to private places, but there's a much broader concern the public should have," said Elisabeth Holmes, a staff attorney at the nonprofit Center for Food Safety. "Public health issues, food safety issues, environmental issues: all those things can be exposed through undercover investigations."

The first-ever ag-gag prosecution, involving a Utah woman who took roadside videos of cows at a Draper City slaughterhouse, was announced this this week. Charges were soon dropped, but the incident hinted at a future in which farms are largely hidden from public sight.

Ag-gag laws were passed in Iowa, Missouri and Utah in 2011 and 2012, and submitted for consideration in ten state legislatures – Arkansas, California, Indiana, Nebraska, New Hampshire, New Mexico, Pennsylvania, Tennessee, Wyoming, and Vermont – this year. Broadly speaking, they make it illegal to take photographs or videos without farmer consent, though some go further. Pennsylvania's proposed law, criminalizes downloading such material over the internet.

The laws have drawn disapproval from many quarters, including the American Civil Liberties Union and the National Press Photographers Union, who say they threaten public discourse, though most criticisms focus on abuse of animals that might go unchecked in the absence of activist attention.

Against these criticisms, farm industry advocates argue that activists often misportray what actually happens on farms, turning isolated incidents into inflammatory narratives of routine abuse that further anti-meat-eating goals. The industry also portrays undercover video-taking as a violation of farmer rights.

"At the end of the day it's about personal property rights or the individual right to privacy," said Bill Meierling, a spokesman for the American Legislative Exchange Council, a conservative business group that drafted the model for many of the ag-gag laws, to the Associated Press. "You wouldn't want me coming into your home with a hidden camera."

The nation's food, however, doesn't come from people's homes. It comes from farms – and in a food system that's both vulnerable and productive, with a single burger containing meat from multiple farms, making problems at a single facility a potentially national issue, hidden cameras are often the only cameras. Much of what's publicly known about factory farms comes from activities that could soon be illegal.

"It's important for the public to know what's going on inside these operations," said Bob Martin, a policy adviser at Johns Hopkins University's Center for a Livable Future and former executive director of the Pew Commission on Industrial Animal Farm Production. In 2009, the commission concluded that "the current industrial farm production system often posses unacceptable risks to public health, the environment and the welfare of the animals themselves."

In one instructive example of what undercover farm videos can accomplish, the largest meat recall in U.S. history was prompted by the secret 2006 taping of so-called downer cows, too sick or weak to stand, being forklifted into position at a Westland/Hallmark Meat Company plant in southern California.

Downer cows are considered potential carriers of mad cow disease, salmonella or dangerous E. coli strains. More than 143 million pounds of beef, much of it destined for consumption in public school lunch programs and fast food franchises, were eventually recalled, and federal laws against downer cow processing tightened.

Under California's ag-gag bill, the person who took that video would have been a criminal. That bill failed to pass, as did Indiana's, but others remain under consideration. In Tennessee, where undercover videos have spotlighted Tyson Foods chicken farms, an ag-gag bill is now awaiting the Governor's decision.

Aside from specific incidents of abuse, undercover videos have also drawn attention to industry practices that are routine but unhealthy, such as housing chickens in dark, befouled battery cages. Criticized by animal welfare advocates on ethical grounds, the cages also hasten the sickening of birds and spread of salmonella. Such conditions in turn lead to human illness and, more perniciously, antibiotic overuse that spawns drug-resistant superbugs.

"The reason these are public health issues, and not just animal rights issues, is that those unsanitary conditions provide breeding grounds" for disease, said Holmes.

Environmental abuses, such as groundwater-contaminating manure "lagoons" outside hog farms, may also be documented by activists. Monitoring farm pollution is ostensibly the job of federal regulators, but the agriculture industry stalled Environmental Protection Agency plans to clean up manure lagoons.

"Not only is EPA not doing the job, but ag gag laws could prevent concerned citizens from doing the job where EPA fails and industry refuses," said Holmes. As for farm animals, the Department of Agriculture has far too few inspectors to do the job well, and many farms are exempted altogether from workplace inspections.

"There isn't very much oversight at the farm," said Gail Hansen, a veterinarian and epidemiologist who's now the senior officer for the Pew Campaign on Human Health and Industrial Farming. Hansen said that third-party monitoring, such as by independent companies, is also absent. Activists fill a largely vacant oversight niche.

Martin credited activist investigations with drawing mainstream attention to factory farming, which in turn supports food safety efforts. "Public health officials aren't allowed inside," he said. "The only glimpse we get is when we see these types of videos. The industry loves to operate in secret."

Undercover Humane Society video still of pigs at Wyoming Premium Farms, where five employees were found guilty of animal cruelty. Image: HSUS

Emily Meredith, communications director of the Animal Agriculture Alliance, a farm industry advocacy group, said videos are often misleading, designed to discourage the public from eating meat.

"The industry feels the ultimate goal of the videos is disingenuous," said Meredith. "Some of the videos have highlighted some bad actors and bad instances of abuse, but I want to make very clear that the industry doesn't condone abuse."

She said the industry has taken steps to police itself, including inviting veterinarians and scientists to review undercover videos for the Center for Food Integrity, an industry advocacy group.

Charlie Arnot, the Center for Food Integrity's CEO, echoed Meredith's insistence that animal mistreatment on farms is rare. He declined to comment on specific ag-gag laws, but said that "we'd encourage people to be as transparent about processes in agriculture as possible."

"We don't think closing barn doors and prohibiting cameras is the right thing to do," said Arnot. At the same time, though, he said undercover investigations are not a solution, and even cameras on every farm wouldn't suffice.

The industry needs to make it easier for farmers and farm employees to report animal abuse, said Arnot, and to foster a working environment in which mistreatment is not tolerated. "I think the answer is to create and maintain a culture of animal care, and to be careful about what we do," he said. "I think that culture exists in most places today."

Said Martin, "When things are hidden from view, it's really hard to tell what's happening. It's hard to know what's being done that could impact public health."