Over the past decade, rising youth use of e-cigarettes and other electronic nicotine delivery systems (ENDS) has prompted aggressive regulation by state and local governments. Between 2010 and 2019, ten states and two large counties adopted ENDS taxes. Applying a continuous treatment...

Recreational marijuana laws (RMLs), which legalize the possession of small quantities of marijuana for recreational use, have been adopted by 18 states and the District of Columbia. Opponents argue that RML-induced increases in marijuana consumption will serve as a "gateway" to harder drug use...