After reviewing empirical research published since 2006 on the effects of the minimum legal driving age (MLDA), Boston University researchers concluded that keeping the MLDA age at 21 reduces the rates of drunk driving, alcohol-related crashes, and underage drinking. The researchers reviewed original research studies and reviews of such studies conducted by other researchers.
The review included a 2009 study, which the researchers found presented “especially convincing evidence on the impact of the age 21 MLDA.” That study examined Fatal Analysis Reporting System data for 1982-2004 to determine how the law affects the ratio of drinking to nondrinking drivers under age 21 involved in fatal crashes. The study found that the MLDA “was independently associated with a 16% decline in the ratio of drinking to nondrinking drivers under age 21 involved in fatal crashes.”
In an NPR Shots article about the review, the lead researcher stated that even though the minimum age law is widely disobeyed, “the weight of the evidence suggests that it….does have a protective effect.”
The researchers also reviewed studies that looked at drinking habits in other countries, including New Zealand, which lowered its drinking age from age 20 to 18 in 1999. Among other things, the New Zealand studies found that lowering the drinking age resulted in (1) more alcohol-related car accidents involving 15- to 19-year olds than would have occurred had the law not been changed and (2) increased drinking among 16- and 17-year olds.
