Starting in the 1980s, people all over the world began to feel disgusted by veal, when the treatment of baby cows was exposed: Veal was produced by separating baby cows from their mothers and raising them in tiny crates where they could barely move. Many people decided to draw a line and refrain from eating veal because it came from such abject suffering. The controversy over veal underscored an ethical concept that dates to some of the earliest animal protection efforts: When it comes to raising animals to be killed for food, some practices are too cruel to stomach.

Concern for the welfare of farm animals is not new. The earliest societies for the prevention of cruelty to animals campaigned against inhumane transportation and slaughter of animals. The earliest federal animal protection statute, the Twenty-Eight Hour Law of 1873, sought to alleviate the suffering of animals carried interstate by railroad from western ranges to eastern stockyards. In 1906, Upton Sinclair’s powerful exposé of the Chicago meatpacking district revealed the many cruelties of industrial slaughter and processing. This was something animal advocates sought to remedy in 1958 with our successful campaign to pass the federal Humane Methods of Slaughter Act. Today, the welfare of animals raised for food is an even greater priority, and the 21st century has seen a dramatic increase in energy, effort and resources targeting the kind of intensive confinement that veal calves typically suffered.

So, it is only natural that after the outrage in response to the treatment of baby veal calves, a heightened awareness of the torment currently experienced by millions of pregnant pigs should follow, particularly because a case regarding inhumane farming practices involving pigs has been in the news so much lately. Currently, the U.S. Supreme Court is considering its ruling in National Pork Producers Council v. Ross. The case centers on Proposition 12, California’s law requiring that pork, veal and egg products sold in the state—no matter where they come from—be sourced from animals housed in spaces that allow them freedom of movement. This has not been common practice in the pork industry. Instead, pregnant pigs are kept in crates so small they can’t turn around—indeed, they can barely take one step for most of their lives. We have documented pregnant pigs in gestation crates (also known as “gestation stalls”) suffering from such distress that they gnaw on the bars of their crates until their mouths bleed.

For decades, we’ve argued against gestation crates and other intensive confinement, raising awareness in corporate boardrooms, shareholder meetings, legislatures, scientific conferences and most importantly in the court of public opinion. As a result, 10 states ban or restrict the use of gestation crates for sows, nine states ban or restrict the use of veal crates, and 11 states ban the use of battery cages for hens—the intensive confinement equivalent for egg-laying hens. In addition, eight states ban the sale of eggs that come from battery cage facilities, and two—Massachusetts in addition to California—ban the sale of veal and pork products from facilities using cruel confinement.

There is scientific evidence that animals cannot thrive when crammed into small cages, and 378 veterinarians and animal welfare scientists submitted an amicus brief to the U.S. Supreme Court to explain this. “Gestation crates hurt pigs,” they asserted. “Dozens of peer reviewed studies provide clear scientific evidence, using well-established indicators, that the welfare of a pig confined to a gestation crate is poor for most of her life. Gestation crates deny pigs the ability to engage in almost every natural behavior. Even the minimal movement of turning around (which a pregnant pig will do almost 200 times daily if given room) becomes impossible.”

There are reasons even beyond cruelty concerns to oppose the intensive confinement of pigs, as some of the submitted amicus briefs detail. Confining mother pigs to crates so small the animals can’t even turn around “induc[es] high levels of stress,” explains the brief submitted by the American Public Health Association and other public health organizations, with experts in zoonotic disease. Stress “severely suppresses” the pigs’ immune systems, and the immune systems of their piglets, making both the mothers and the babies “more susceptible to disease.” The use of gestation crates creates alarming health and safety risks for humans as “infectious diseases will persist in the piglets through slaughter without detection, resulting in pork products contaminated with pathogens carried by piglets.” The federal government estimates that roughly half a million Americans are sickened every year by contaminated pork, and pigs are “ideal mixing vessels,” the brief says, “for various strains of influenza virus, including human influenza. Intensive confinement increases the chances that a strain of influenza carried by pigs will ‘jump’ to humans.”

Another reason to fight gestation crates is concern for worker safety, as workers are first to be at risk for diseases that fester in intensive confinement systems. Worker safety advocates submitted a brief, too, making a strong case against gestation crates for the health and safety of workers: “Slaughterhouse workers, drivers, and livestock auction employees all live in California, where they interact with the animals or their carcasses prior to the meat entering the marketplace …. These workers will thus have a meaningfully increased risk of immediate infection if Proposition 12 cannot take effect.” This brief also connects the health of workers to public health in general, since workers can return home and infect family members with diseases incubated in over-stressed pigs.

Already, responsible farmers are refusing to use gestation crates for pregnant sows, and even some major meat companies have voluntarily taken a stand against the practice (one even submitted a brief in support of Proposition 12). Placing a ban on the in-state use of cruel confinement or sale of cruel products through a law like Proposition 12 is a major step forward for animal welfare and public health and safety.

We’re awaiting the Supreme Court’s decision in the NPPC case with hopeful anticipation that the Court will affirm the constitutionality of Proposition 12. And while we cannot predict their decision, which is expected to come early this year, this case has already put a spotlight on the abject cruelties of the pork industry, causing compassionate consumers to object much like they did to veal in the 80’s. We’re certain of one thing: Whatever the decision of the court, we’ll carry the fight to eliminate gestation crates through to the finish. One way or another, pork’s days as a product of callous indifference and abject cruelty are numbered.

Sara Amundson is president of the Humane Society Legislative Fund.