The effect of internal possession laws on underage drinking among high school students: a 12-state analysis.

Objectives: We assessed the effect of internal possession (IP) laws, which allow law enforcement to charge underage drinkers with alcohol possession if they have ingested alcohol, on underage drinking behaviors.

Methods: We examined Youth Risk Behavior Survey (YRBS) data from 12 states with IP laws and with YRBS data before and after each law's implementation. We used logistic regression models with fixed effects for state to assess the effects of IP laws on drinking and binge drinking among high school students.