Their case invoked one of America's most cherished principles: the free-speech guarantee in the First Amendment of the Constitution. The public gallery was filled as close to 200 people came to hear the argument in the U.S. Court of Appeals, the second-highest court in the country.
According to a coalition of industry groups from the three North American countries, foundational speech rights are violated when meat companies are forced to stamp, "Born in Canada," or "Born in Mexico," on their packaging.
They say country-of-origin labelling isn't just costly, from a logistical standpoint. They say it also amounts to the government forcing them to divulge information, against their will and without justification, in breach of the principles espoused by America's founding fathers.
The multiple parties with standing in the case were represented by a pair of attorneys: a federal lawyer who argued on behalf of the U.S. government, against an opponent who represented meat-industry groups.
The industry attorney argued that the rules are nothing more than protectionism, disguised as an attempt to help consumers learn about the origin of their food. She said the rules did not meet the standard set by past court cases about what corporations need to disclose.
"We're here representing ranchers who are feeling a colossal impact," said Catherine Stetson, arguing for the American Meat Institute and its Canadian-Mexican allies.
"(Proponents of labelling) want to favour meat that is born, raised and slaughtered in the U.S."
U.S. rules on country labels, introduced in 2002 and enforced since 2008, are blamed for reducing Canadian cross-border meat exports by half. The provisions are opposed by various elements in the U.S. meat industry — but are supported by some border-area ranchers who compete with Canadians and Mexicans, and by their allies in Congress.
The labelling rules are also being fought at the World Trade Organization.
In the U.S. court system, a lower-court judge sided against the meat coalition's speech argument. District Court judge Ketanji Brown Jackson, appointed by President Barack Obama, concluded last year that free-speech standards applied differently to corporations.
In a rare reversal last month, however, the country's second-highest court agreed to hear the case. The surprise announcement from the U.S. Court of Appeals came just a few days after a panel of three judges declared they would not take it on.
Oral arguments were held Monday. Attorneys for the opposing sides answered questions from 11 judges at the Court of Appeals.
The lawyer speaking for the U.S. government insisted the labelling rule had legitimate aims. He said the goal was to help consumers — not give the domestic industry a protectionist advantage.
"It's furthering consumers' ability to act on their own preference," said Daniel Tenny, the U.S. Department of Justice lawyer.
"We're not directly trying to help American ranchers... (although) it might have that effect."
That federal lawyer received a rough ride from one judge appointed by George W. Bush. Brett Kavanaugh repeatedly pressed Tenny to explain how the rules did anything to help consumers.
He suggested the legal precedent says governments cannot force companies what to say, except under three circumstances: to protect health, safety, and consumers from being deceived.
Kavanaugh suggested the labelling rules did not meet that standard — but served other purposes.
"This is a bias against Mexican and Canadian ranchers," the judge said. "It's a traditional protectionist impulse. What's the difference?"
Later in the hearing, he added: "The implicit message is to buy American."
The questions for the federal lawyer were a little gentler from another judge appointed by Obama, Cornelia Pillard.
She suggested, in a question to Tenny, that perhaps the rule could even help — not hurt — Canadian and Mexican producers, if their safety standards were better and it served to let American consumers know that they were getting a superior product.
Tenny agreed with her.
After more than two hours of hearings, the judges adjourned to consider the arguments. It's unclear when a verdict might be rendered.
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