Scoring the Strengths and Weaknesses of Underage Drinking Laws in the United States

Introduction: To prevent or reduce underage drinking, all states have adopted various laws that apply to youth, youth driving, and providers of alcohol. For example, since drivers under age 21 are not supposed to consume any alcohol, zero tolerance (ZT) laws were adopted that provide for lower blood alcohol concentration limits for drivers under age 21. Laws making it illegal for youth to use fake identification to purchase alcohol have also been passed in every state. Other Minimum Legal Drinking Age of 21 (MLDA-21) laws focus on affecting the behavior of those who sell or furnish alcohol—for example, laws prohibiting hosting underage drinking parties and civil liability laws targeting commercial and noncommercial providers of alcohol to underage youth.

Methods: The primary source for data on underage drinking laws in the United States is the National Institute on Alcohol Abuse and Alcoholism’s Alcohol Policy Information System dataset. Theoretically, a law that is strong, is able to be enforced, has few or no exceptions, and has meaningful sanctions for any violations should have a general deterrent effect on the behavior of would-be violators. On the contrary, a law that is weak, is difficult to enforce, has numerous exceptions, and has limited—if any—sanctions should not have the same general or specific deterrent effect. The 20 MLDA-21 laws used in this study were scored based on (1) the sanctions enacted for violating the law; (2) any exceptions or exemptions affecting the application and enforcement of the law; and (3) any provisions that could affect the law or its enforcement negatively or positively.

Results: There was a statistically significant difference between weak laws and strong laws on both the rates of drinking drivers under age 21 in fatal crashes and the per capita beer consumption. An inspection of the mean scores indicated that stronger laws demonstrated slightly improved crash ratios for drinking drivers under age 21 (M = 0.24, SD = 0.12) and per capita beer consumption (M = 1.22, SD = 0.19) when compared to weaker laws (M = 0.35, SD = 0.23 and M = 1.32, SD = 0.23, respectively).

Conclusions: This study demonstrates that although an absent/present, before/after analysis of law implementation may yield useful information, the inclusion of the law strengths provides a more accurate understanding of the impact of laws on related outcomes. By assessing and coding the strengths of laws, future analyses will more accurately evaluate their effect. Public health officials and policymakers can then make informed decisions on recommending and introducing legislation that can potentially save lives and reduce injuries.