The court largely ignored the merits of the ban in the 20-page ruling but determined the city's Board of Health engaged in policy-making, and not simply health regulations, when it imposed the restrictions on restaurants, delis, movie theaters, stadiums and street cart vendors.
"The Board of Health engaged in law-making beyond its regulatory authority," the opinion reads. "... It is clear that the Board of Health wrote the Portion Cap Rule without benefit of legislative guidance."
The city had hoped Thursday's ruling would overturn a lower court's decision that blocked the restrictions after restaurants, theater owners, beverage companies and small stores sued.
In oral arguments earlier this month, attorneys for the city argued that sugary drinks are the largest source of added sugar in the American diet. They argued the restrictions were based on science, and weren't a true ban, only a limit on cup size.
Several judges on the Court of Appeals questioned where the board would draw the line.
Judge Eugene Piggott Jr. asked whether triple-decker burgers would be next. Judge Victoria Graffeo questioned the limit in light of exclusions like mixed coffee drinks loaded with more than 800 calories.
According to the American Beverage Association, New York City is the only jurisdiction attempting such a restriction, though several others around the country have tried and failed to impose special taxes on sugary drinks.
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