For more than a decade, foie gras producers have been fighting to stop California from banning foie gras.

Their argument: that some states imposing different, higher animal welfare standards violates the commerce clause of the US Constitution (which leaves the regulation of interstate commerce up to the federal government), or alternately violates federal laws about the production of poultry products.

They haven’t met with much success in court. While one federal judge overturned the foie gras ban in 2015, that decision was later overturned by the Ninth Circuit, and the ban went back into effect when the Supreme Court declined to hear the case last year. The courts have also struck down trickery such as restaurants giving away foie gras with purchase of an expensive tasting menu. After that, foie gras advocates sued again — and last week, the courts found against them again.

The latest ruling reaffirms that the federal government doesn’t have the authority to stop states from imposing their own animal welfare requirements. And while foie gras is a tiny fraction of animal farming, the ruling has implications for more expansive welfare laws, too.

Lots of states want to regulate animal cruelty. The courts are mostly agreeing they can.

In the past decade, voters in lots of states have imposed various animal welfare-related restrictions on the meat, dairy, and egg products sold in their state. The biggest of those was California’s Proposition 12, which bans the sale of meat and eggs from caged animals. It followed on the heels of a similar 2016 Massachusetts law, as well as foie gras bans in California and New York City; battery cage bans in Michigan, Ohio, Rhode Island, and Washington; and bans on gestation crates for pregnant pigs in Arizona, California, Colorado, Florida, Maine, Michigan, Ohio, Oregon, and Rhode Island.

After many of these laws were approved, meat industry groups sued, in some cases joined by other states. Their justification? No state ought to be allowed to impose any animal welfare standard above the standards set forward by the federal government. Laws like these, they argued, impede interstate commerce. (The states argued that they had standing to sue because their residents, as well as state institutions like prisons, would pay higher prices for animal products whose production was changed to be compatible with animal welfare laws.)

If that argument were to succeed in court, it wouldn’t just mean that foie gras could be served in California. It would effectively mean that a core strategy of the movement against animal cruelty in factory farming — slowly convincing voters, state by state, that specific practices are unethical and should be banned — was impossible.

Instead, any fight to reduce cruelty in animal agriculture would have to happen in Congress, which is much more favorable territory for factory farms and their lobbyings. While voters have overwhelmingly supported laws to reduce animal cruelty, legislators have been distinctly more inclined to drag their feet. The last major federal bill targeting farm animal welfare was introduced in 2010, and it never passed.

So it’d be a big victory for factory farms if they were able to ban states from considering their own animal welfare restriction and take the fight to the more favorable territory of Congress.

But courts haven’t been persuaded.

What the court had to say about California’s much-contested foie gras ban

California’s foie gras ban passed in 2004, but the state phased it in gradually; foie gras wasn’t fully prohibited until 2012. Then producers sued. In 2015, the ban was overturned by a federal judge who found California was unconstitutionally attempting to override federal poultry law. Foie gras returned to restaurants. The state appealed to the Ninth Circuit, which ruled 3-0 in 2017 that the lower court had erred in overturning the ban. Foie gras advocates appealed again, this time to the Supreme Court, but early last year, the Supreme Court declined to hear the case, making the Ninth Circuit’s decision final.

Some people thought that would be the end of the foie gras legal fight. Instead, the plaintiffs sued again. The US District Court for the Central District of California seemed unimpressed to be revisiting the issue. It ruled in favor of the ban, complaining that the plaintiffs had presented “substantially the same challenges they brought up in the first case.”

The plaintiffs said in a statement they intend to appeal the ruling again.

The decision “affirms that state lawmakers and governors have a right to set standards for humane treatment, if they choose to do so,” Kitty Block, CEO of the Humane Society, wrote.

That’s a big deal because the vast majority of animals raised for food in the US are now factory farmed, often in horrific conditions. And while the majority of Americans still eat meat and aren’t ready to go vegetarian, most of them oppose the conditions on factory farms and in slaughterhouses, and most of them support animal cruelty measures when they get the chance to vote on them. Those laws not only improve conditions for billions of animals but also offer a route toward a world without factory farming. If one state can figure out how to ban cruel conditions while still offering the food its citizens love (perhaps by leaning heavily on plant-based and cell-cultivated meat options), then similar laws will have the chance to sweep the rest of the nation.

At their best, America’s states function as laboratories of democracy that test policies so other states can learn from them and adopt the best ones. Permitting that kind of experimentation here will help bring about the end of animal cruelty much sooner.

Related We could end factory farming this century

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