In the early 1980s, researchers began to compare the rates of teen traffic fatalities in states with a drinking age of 21 versus those with one of 18. The resulting statistics startled legislators and prompted them to pass the Federal Uniform Drinking Age Act (FUDAA), which withheld federal highway funding from states who kept their drinking age below 21. Although this law essentially gave the federal government control of an issue previously delegated to states, the Supreme Court ruled in favor of the act, maintaining that the high national rate of teen accidents called for federal intervention. Since then, the assumption that a higher drinking age reduces alcohol-related traffic fatalities has remained unchallenged. But as Jeffrey Miron and Elina Tetelbaum, of Harvard and Yale, respectively, argue in their new study, “Does the Minimum Drinking Age Save Lives?”, this widely held public belief may be based on a misinterpretation of the available data.

     When judging the effectiveness of FUDAA, researchers have traditionally focused on the period immediately following its enactment in 1986 and have failed to control for confounding variables such as improved safety features in automobiles and different state speed limits. The teen traffic fatality rate per mile driven has been falling since the late sixties, nearly 20 years before the federal drinking age was set at 21. The decline immediately following the FUDAA was a part of a much larger trend. While there was a significant initial drop in fatalities after the enaction of FUDAA, the rate of decrease slowed within two or three years to what it had been before the act was passed.

     It is important to note that federal statistics used to justify the drinking age measure traffic fatalities in general – not necessarily alcohol-related collisions. The lower rate of fatalities may be due to more numerous hospitals and better medical treatments, instead of a fall in the rate of collisions. As Miron and Tetelbaum note, many other confounding variables plague the data: the states that showed the most significant drop in teen traffic fatalities after FUDAA were those that voluntarily implanted the law before the 1986 deadline. These states were also those most likely to enforce other traffic and safety measures such as lower speed limits. When the researchers controlled for these and other variables, the correlation between a minimum drinking age of 21 and fewer teen fatalities disappeared. In fact, in nine states it appeared that the higher drinking age had temporarily increased the fatality rate. There was no overall trend, the authors conclude, and no demonstrable long-term benefit from the FUDAA.

     The purpose of the Federal Uniform Drinking Age Act, when it was written in 1984, was to reduce teen traffic fatalities. Many claim it has achieved its goal.  However, a less myopic view of the data, one that takes other variables and long-term trends into account, reveals that its impact on fatalities has been slight – if not non-existent. The FUDAA also represents an intrusion by the federal government on states’ rights, and can additionally be linked to an increase in binge drinking among underage drinkers. These unfortunate externalities might be more tolerable if the FUDAA were indeed effective at lowering fatalities among young drivers, but Miron and Tetelbaum convincingly argue that it isn’t. Even if one is not completely persuaded by their argument, it remains clear that the issue deserves to be re-examined.

Jeffrey Miron is the Director of  Undergraduate Studies for the Economics Department at Harvard University. Elina Tetelbaum is a member of  the Yale Law School Class of  2010. The full text of  the article can be read at http:// papers.ssrn.com/sol3/papers.cfm?abstract_id=1000359.

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