There are a lot fewer cages in factory farms now than there were 10 years ago. Much of this change was spearheaded by Jon Lovvorn, chief counsel of animal protection law for the Humane Society of the United States.

Putting animals in tiny cages not only limits their movement and increases their suffering, but creates dirty conditions that make them even more susceptible to disease. California’s Proposition 12 prohibits the sale of eggs, veal, and pork raised this way — and as California imports most of its pork from other states, the law has had a major impact on the pork industry nationwide. The industry lobby challenged Prop 12 after it was passed by ballot measure in 2018, and the lawsuit was eventually appealed to the Supreme Court.

Lovvorn led HSUS’s legal defense of the law, and in May, his team’s effort paid off: The Court ruled 5-4 in favor of California. It’s a landmark decision; according to Lovvorn, “It’s the first time the Supreme Court has ever ruled in favor of animal welfare.” As Vox’s Kenny Torrella has reported, the decision means that once the law is fully implemented, 1 million pigs, 40 million hens, and tens of thousands of calves will be freed from cages each year.

Prop 12’s victory before the Supreme Court was undoubtedly a win for animal rights, but there’s still so much left to do. Industrialized, large-scale animal agriculture has wide-ranging consequences on biodiversity as a whole: it generates more than a third of the world’s methane emissions, pollutes water systems, and cuts down available habitat for wild animals.

In the face of climate change and a business-as-usual approach, 16 percent of total species, or 147 billion animals, could die over the next 20 years, according to Lovvorn — and that may still be a low estimate. Incremental temperature changes will destroy the ability of some animals, like arctic aquatic animals, to survive. Some animals will die in forest fires, and many will drown in floods. The plight of wild animals isn’t independent from those that are caged.

To tackle the wicked, entangled problem of climate change and factory farming, Lovvorn works as a co-chair for the Climate, Animal, Food, and Environmental (CAFE) Law and Policy Lab at Yale Law School. There, he teaches classes on animal law and climate policy. The lab hopes to facilitate a new way of approaching law and policy that connects climate, food, animals, and environment as interrelated justice issues. Its mission is to create legal and policy strategies that can be adopted to make industrial food producers accountable for their negative effects, such as the welfare of the animals, pollution, and the effects on the environment. CAFE also makes its work open source, so that nonprofits, policymakers, and students can use these resources freely.

As an academic, Lovvorn has argued for reframing how we think about food. In an insightful 2018 paper, he points out the huge gap in how US law treats dirty, inefficient energy production compared to food production (which is, after all, a form of energy). His work is helping close that gap and align the law with the public interest.

Speaking on the catastrophic effects of climate change on animals, Lovvorn says, “the animals go first — they literally are the canaries in the coal mine.”