"The portion cap rule, if upheld, would create an administrative Leviathan and violate the separation of powers doctrine," by straying into territory that should belong to the elected City Council, not the board appointed by Mayor Michael Bloomberg, Tingling wrote.
That, he wrote, "has the potential to be more troubling than sweetened beverages.
The city Board of Health approved the measure in September. Championed by Bloomberg, it follows on other efforts his administration has made to improve New Yorkers' eating habits, from compelling chain restaurants to post calorie counts on their menus to barring artificial trans fats in restaurant food to prodding food manufacturers to use less salt.
The city has said that while restaurant inspectors would start enforcing the soda size rule in March, they wouldn't seek fines $200 for a violation until June.
Soda makers, restaurateurs, movie theater owners and other business groups sued, asking a judge to declare the measure invalid. In February, they asked Tingling to bar the city from enforcing the regulation while the suit played out.
City officials have called the size limit a pioneering move for public health. They point to the city's rising obesity rate about 24 percent of adults, up from 18 percent in 2002 and to studies tying sugary drinks to weight gain. Care for obesity-related illnesses costs government health programs about $2.8 billion a year in New York City alone, according to city Health Commissioner Dr. Thomas Farley.
The supersize-drink crackdown will "have significant public health effects, and the sooner that happens, the better," city lawyer Mark W. Muschenheim said in court in February.
Critics said the measure is too limited to make a meaningful impact on New Yorkers' waistlines. But they said it would take a bite out of business for the eateries that have to comply, while other establishments still will get sell sugary drinks in 2-liter bottles and supersize cups.
Beverage makers had expected to spend about $600,000 changing bottles and labels, movie theater owners feared losing soda sales that account for 20 percent of their profits, and delis and restaurants would have had to change inventory, reprint menus and make other adjustments, according to court papers.
"These are costs which these businesses are not going to be compensated for," and the money will be wasted if the court ultimately nixes the law, James E. Brandt, a lawyer for the American Beverage Association and other opponents, told the judge in February.
Critics also said the restriction should have gone before the elected City Council instead of the Bloomberg-appointed health board. The city says the panel of doctors and other health professionals had both the authority and expertise to make the decision.