Do State Tobacco 21 Laws Work?

This study is the first to comprehensively examine the impacts of statewide tobacco 21 (T-21) laws on youth tobacco consumption, including spillovers to minor teens. Using data from the 2009-2019 Behavioral Risk Factor Surveillance Survey and a differencein-differences approach, we find statewide T-21 laws are associated with a 2.5 to 3.9 percentage-point decline in smoking participation among 18-to-20-year-olds. Next, using data from the 2009-2019 State Youth Risky Behavior Surveys, we find that statewide T-21 laws reduced cigarette and electronic cigarette (e-cigarette) consumption among 18-year-old high school students. However, the negative impact of T-21 laws on e-cigarette use among 18-year-olds may be partially blunted by an increase in borrowing e-cigarettes. Finally, we find that T-21 laws generate important spillovers, including (i) reductions in cigarette use among 16-to-17-year-olds, a group that relies heavily on “social markets”, and (ii) reductions in marijuana use and alcohol consumption among older teenagers