The roots of California's new law that raises the smoking age to 21 are in a small town west of Boston.
In 2005, Needham became the first municipality in the United States to ban tobacco sales to anyone under drinking age.
While some public health officials had long advocated such a move, Stanton Glantz, the director of the Center for Tobacco Control Research and Education at UC San Francisco, was skeptical it would have any effect.
Glantz and others thought that young adults in Needham, a 12-square-mile city, could get cigarettes from older peers or go to neighboring cities for their tobacco.
"I started out thinking it was a waste of time," Glantz admitted.
But the results were dramatic. Between 2006 and 2010, teen smoking rates in the 30,000-person city fell from 13% to 7%, according to a study published last year in Tobacco Control.
During the same time, the smoking rate in 16 neighboring communities where 18-year-olds could buy tobacco fell from 15% to 12%, according to the study.
The smoking rate for adults in Needham is 8%, nearly 10 percentage points less than for the rest of the state, according to the Massachusetts Department of Public Health.
"I changed my mind," Glantz said. "I now think [raising the smoking age] is good public policy."
Many others, including Gov. Jerry Brown, agree. Since 2005, the state of Hawaii, New York City and dozens of towns in Massachusetts, New Jersey and Ohio have also raised the smoking age.
Micah Berman, a professor of public health and law at Ohio State University, said he doubts so many municipalities would have changed their laws if Needham's smoking rates had not changed so dramatically.
"It really was the numbers that came out of Needham that were the spark that led to so much change," he said.
Glantz said he underestimated the effect the age limit would have. Nearly 90% of people who give cigarettes to minors are also underage themselves, according to the Tobacco Control study, so raising the minimum smoking age would make it more difficult for teenagers to find a source for tobacco, Glantz said.
"While lots of high-schoolers hang out with students that are 18, they don't hang out with people who are 21," he said.
Timothy McDonald, Needham's director of public health, said that the law has led to long-term changes in the city.
"Not smoking now is becoming more the norm," he said.
The town conducts compliance checks at stores that sell tobacco. So far this year, the town has issued only one citation for illegal sales, down from four in 2015 and seven the year before.
And, perhaps more important, McDonald said, more neighboring towns have also raised their smoking ages.
"That's when you get a real public health effect, when more and more communities change their laws," McDonald said.
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