The Canadian women's ice hockey team is supposedly in hot water after some of its members were drinking beer on the ice to celebrate winning against the American team in the Vancouver Olympics. At least one of them was 18, and the drinking age in British Columbia is 19 (but 18 in Alberta where they trained, as well as in the player's native Quebec). They weren't out of control, and the festivities occurred after the fans had left.
The American media has been making a big deal out of this. Why? Because in the good old US of A, the drinking age is 21, and many older adults are both terrified and titillated simultaneously at the idea of those under 21 drinking. Especially when it is done by young women. Thus it makes a good story over here. But the rest of the world (including Canada) just laughs at our puritanical immaturity and cultural schizophrenia regarding alcohol and young people.
In Canada, they recognize 18-20 year olds as full adults, and treat them as such. The drinking age is 18 or 19, depending on the province, and they do not appear to be any worse off for it than us. Drinking at that age is viewed as normative behavior, and they recognize that alcohol abuse (rather than mere use) is the real problem. Perhaps we can learn a thing or two from our neighbor to the north.
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Saturday, February 27, 2010
Friday, February 19, 2010
Vermont Debates the Drinking Age
The Vermont legislature is currently debating whether or not to lower the drinking age to 18. And we hope they choose to do so. Someone's gotta go first, and Vermont's independent streak will make them a good choice.
For those who don't know, Vermont was the first state (except the 10 states that were 18 since the 1930s) to lower the drinking age from 21 to 18 in 1971, along with the voting age and age of majority. This remained the case until 1986, when it was raised back to 21 due to federal coercion. Actually, Governor Richard Snelling flat-out refused to raise the drinking age in spite of the highway funding penalty, vetoing several bills, and thought that it would be better to actually get tougher on drunk driving and improve alcohol education. It was not until they got a new governor that the state finally sold out and it was raised.
Interestingly, Vermont in 2008 actually had zero under-21 drunk driving fatalities, down from 14 in 1982. Of course, that's easy for a state with a population of only 621,760. And the decline began at least four years before the drinking age was raised. This is in spite of their proximity to Quebec (where the drinking age is 18), the state's rural nature, and its above-average "binge" drinking rate. Since the pretext for raising the drinking age in the 1980s was reducing drunk driving, many of the state's 18-20 year olds are probably now wondering, "Can we have our civil liberties back now?"
Most states either hate guns or hate gays. Vermont, however, uniquely tolerates them both. And if they lower the drinking age to 18, they will truly be the most free state in the country. Even freer than their neighbor New Hampshire, the one with the motto "Live Free or Die," which also happens to be the motto of the True Spirit of America Party.
For those who don't know, Vermont was the first state (except the 10 states that were 18 since the 1930s) to lower the drinking age from 21 to 18 in 1971, along with the voting age and age of majority. This remained the case until 1986, when it was raised back to 21 due to federal coercion. Actually, Governor Richard Snelling flat-out refused to raise the drinking age in spite of the highway funding penalty, vetoing several bills, and thought that it would be better to actually get tougher on drunk driving and improve alcohol education. It was not until they got a new governor that the state finally sold out and it was raised.
Interestingly, Vermont in 2008 actually had zero under-21 drunk driving fatalities, down from 14 in 1982. Of course, that's easy for a state with a population of only 621,760. And the decline began at least four years before the drinking age was raised. This is in spite of their proximity to Quebec (where the drinking age is 18), the state's rural nature, and its above-average "binge" drinking rate. Since the pretext for raising the drinking age in the 1980s was reducing drunk driving, many of the state's 18-20 year olds are probably now wondering, "Can we have our civil liberties back now?"
Most states either hate guns or hate gays. Vermont, however, uniquely tolerates them both. And if they lower the drinking age to 18, they will truly be the most free state in the country. Even freer than their neighbor New Hampshire, the one with the motto "Live Free or Die," which also happens to be the motto of the True Spirit of America Party.
Sunday, February 14, 2010
Social Host Laws Revisited
We at Twenty-One Debunked have repeatedly stated that there was no hard evidence that "social host" laws (laws that impose civil and/or criminal liability on those who merely allow (not give) those under 21 to drink on property they control, especially if injuries or fatalities subsequently occur) save any lives or reduce underage drinking. In fact, a 2008 study by Fell et al. (a true believer in the 21 drinking age no less) found no effect of such laws, at least not for criminal ones. That is not surprising since even district attorneys find these laws difficult to enforce, including the notorious law in Massachusetts.
But a new study by Dills (2009) appears to have found a lifesaving effect for social host laws among 18-20 year olds, at least according to the author. And it supposedly remained even after several other variables (drinking age, 0.08 BAC limit, seat belt law, zero tolerance, beer tax, etc.) and fixed effects were controlled for.
However, this claim does not appear to stand up to closer scrutiny. After reading the paper ourselves, we find the following issues with the study:
In other words, the evidence from the study in support of social host laws is rather weak, and is likely to be a spurious correlation. In fact, the reported 9% decrease in drunk driving fatalities is both too small to be conclusive evidence of causality (especially when statistical significance is examined), and too large to be plausible given that the majority of people are likely unaware of the existence of these laws, especially civil ones (which are usually only sporadically enforced). Most likely, social host laws are acting as a proxy for something else, such as tougher DUI laws and/or enforcement.
To our knowledge, there has been only one other study of social host laws to date. A 2000 study by Stout et al. did manage to find a significant negative correlation between all-ages civil social host laws and both self-reported "binge" drinking as well as self-reported drinking and driving among adults over 21 in national survey data from 1984-1995. While numerous variables were controlled for, the following were not: state fixed effects, state trends, blood alcohol limit, sobriety checkpoints, overall DUI enforcement, and drinking age. Again, it could have been a proxy for something else. And traffic fatalities or any other consequences of drinking were not examined in the study, so questions relating to those are left unanswered by that study. Generalizability is also limited, and it says nothing about the persistence of the reported effects or whether they are applicable to anyone under 21, especially in today's world. Those who use the study to justify social host laws as worthwhile should bear in mind that the same study found that mandatory fines and especially mandatory jail for a first DUI offense to be more effective in reducing self-reported drinking and driving than social host laws.
What about the "collateral damage" that occurs from social host laws? For one, a host (however broadly defined) can be fined, sued, or even jailed--in some cases for several years. And civil liberties often need to be violated to enforce such draconian prohibitions. But what about the "children," you know, the ones these laws were ostensibly written to "protect"? In the five years since San Diego passed their own local social host ordinance in 2003 (California itself has none), there have been more police responses to parties, and more alcohol-related teen hospital admissions. In other words, there was likely just as much drinking if not more so, but the bigger teen drinking parties of the past seem to have broken up into many more smaller (and more dangerous) ones with presumably more booze to go around. And only the bold and reckless (and/or ignorant) are hosting them now that it is a crime. Looks like the Law of Eristic Escalation in action yet again.
We at Twenty-One Debunked do not support any type of social host law, civil or criminal, as they contravene the very idea of personal responsibility and likely do more harm than good by forcing alcohol deeper underground, making it more dangerous than it has to be. At the very least, we do not think that such laws should apply to drinking by those over the age of majority (18), regardless of the current legal drinking age. Of course, we want that to be 18 as well. And we have repeatedly noted that social host laws are just another pathetic attempt to prop up the greatest alcohol policy failure since Prohibition. We would be better off going after those who actually do drive drunk and endanger the public, regardless of age.
But a new study by Dills (2009) appears to have found a lifesaving effect for social host laws among 18-20 year olds, at least according to the author. And it supposedly remained even after several other variables (drinking age, 0.08 BAC limit, seat belt law, zero tolerance, beer tax, etc.) and fixed effects were controlled for.
However, this claim does not appear to stand up to closer scrutiny. After reading the paper ourselves, we find the following issues with the study:
- The fatalities were divided into three categories: drinking, drunk driver, and sober. The fact that data from the 1977-2005 were used would likely introduce biases relating to BAC testing rates. Testing rates were much lower in the 1970s and early 1980s, and determination was often subjective.
- Restricting the data to 1982-2005 (the only years for which that FARS has alcohol-related data, and likely less biased) reduced the size and significance of the effects of both social host laws and the drinking age. The former was only significant at the 10% level, while the latter was not even statistically significant at all.
- None of the models showed a "dose-response" relationship when the effects of various drinking ages (18, 19, 20, and 21) were tested. In fact, some even had the "wrong" sign.
- Many of the covariates such as BAC limit, beer tax, zero tolerance, and seat belt laws were statistically insignificant, suggesting something wrong with the models.
- Dram-shop laws were not controlled for, and since many social host states have these as well, this may be a potent confounding factor. Some past studies have found effects of dram-shop laws, while others have not.
- Other variables that were not controlled for include sobriety checkpoints, roving patrols, 0.10 BAC laws, harsher DUI penalties, administrative license revocation, police per capita, and several others.
- There was no distinction between statutes and case law, which suggests a potential endogeneity problem.
- There was no over-21 comparison group.
- In general, states that adopted social host laws already had declining fatalities before adoption.
- Using survey data among 18-20 year olds, effects of social host laws were not significant (even at the 10% level) for drinking, "binge" drinking, and drunk driving in the past 30 days when other variables and state trends were controlled for. For the frequency of drunk driving per respondent, it was only significant at the 10% level despite a very large sample size of over 52,000 people.
- Effects on those under 18 were not tested in any sense.
In other words, the evidence from the study in support of social host laws is rather weak, and is likely to be a spurious correlation. In fact, the reported 9% decrease in drunk driving fatalities is both too small to be conclusive evidence of causality (especially when statistical significance is examined), and too large to be plausible given that the majority of people are likely unaware of the existence of these laws, especially civil ones (which are usually only sporadically enforced). Most likely, social host laws are acting as a proxy for something else, such as tougher DUI laws and/or enforcement.
To our knowledge, there has been only one other study of social host laws to date. A 2000 study by Stout et al. did manage to find a significant negative correlation between all-ages civil social host laws and both self-reported "binge" drinking as well as self-reported drinking and driving among adults over 21 in national survey data from 1984-1995. While numerous variables were controlled for, the following were not: state fixed effects, state trends, blood alcohol limit, sobriety checkpoints, overall DUI enforcement, and drinking age. Again, it could have been a proxy for something else. And traffic fatalities or any other consequences of drinking were not examined in the study, so questions relating to those are left unanswered by that study. Generalizability is also limited, and it says nothing about the persistence of the reported effects or whether they are applicable to anyone under 21, especially in today's world. Those who use the study to justify social host laws as worthwhile should bear in mind that the same study found that mandatory fines and especially mandatory jail for a first DUI offense to be more effective in reducing self-reported drinking and driving than social host laws.
What about the "collateral damage" that occurs from social host laws? For one, a host (however broadly defined) can be fined, sued, or even jailed--in some cases for several years. And civil liberties often need to be violated to enforce such draconian prohibitions. But what about the "children," you know, the ones these laws were ostensibly written to "protect"? In the five years since San Diego passed their own local social host ordinance in 2003 (California itself has none), there have been more police responses to parties, and more alcohol-related teen hospital admissions. In other words, there was likely just as much drinking if not more so, but the bigger teen drinking parties of the past seem to have broken up into many more smaller (and more dangerous) ones with presumably more booze to go around. And only the bold and reckless (and/or ignorant) are hosting them now that it is a crime. Looks like the Law of Eristic Escalation in action yet again.
We at Twenty-One Debunked do not support any type of social host law, civil or criminal, as they contravene the very idea of personal responsibility and likely do more harm than good by forcing alcohol deeper underground, making it more dangerous than it has to be. At the very least, we do not think that such laws should apply to drinking by those over the age of majority (18), regardless of the current legal drinking age. Of course, we want that to be 18 as well. And we have repeatedly noted that social host laws are just another pathetic attempt to prop up the greatest alcohol policy failure since Prohibition. We would be better off going after those who actually do drive drunk and endanger the public, regardless of age.
Wednesday, February 3, 2010
Let's Talk About Canada
When advocates of lowering the drinking age bring up Europe for comparison, they often paint themselves into a corner. America and Europe are very different, so in many ways it's apples and oranges. But European countries are not the only ones that have lower drinking ages.
We do in fact have a good yardstick for what would have happened had the drinking age not been raised to 21 in the 1980s. It's called Canada. Their drinking ages have remained at 18 or 19, depending on the province, for the past three decades. And it is the country that most resembles America in many ways, especially in terms of its car culture. So let's talk about Canada then.
ALCOHOL-RELATED TRAFFIC FATALITIES
It is often claimed by proponents of the 21 drinking age that raising the drinking age saved lives. While alcohol-related traffic fatalites did decline, correlation does not prove causality. First of all, the trend began in 1982, two years before the National Minimum Drinking Age Act that forced all states to raise their drinking ages to 21 by 1987. Perhaps the trend began even earlier, as total 18-20 year old fatalities began declining in 1979-1980, but 1982 is the first year that FARS has reasonably reliable data for alcohol-related fatalities. And Canada saw a remarkably similar trend, as you can see in the graphs below (courtesy of NHTSA).
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Interestingly, the decline in alcohol-related traffic fatalities since 1982 occurred at about the same rate in both countries, with no evidence of divergence in the expected direction despite the fact that Canada did not raise the drinking age to 21. In both countries, drivers under 21 saw some of the largest declines of all compared with other age groups, though all ages saw some decline over the long run. Moreover, progress continued for Canadian teens from 1997-2005, while unfortunately it stalled for their American counterparts during that time, only resuming after gas prices began to skyrocket (which Americans were not used to) and the economy began to sag. In 2005-2006, the rate of total 15-24 year old traffic fatalities (per 100,000 people) for the USA was 25.5, and 16.9 in Canada, the latter being 33% lower than the former.
In other words, the downward trend in fatalities can be explained entirely by other factors, which likely include, inter alia:
Worse still, according to a 2004 book by Leonard Evans, former safety researcher for General Motors, America has been lagging behind several other countries in terms of traffic safety. The table below shows the change in the number and rate of total traffic fatalites (all ages) over time in the US and three other countries that maintained lower drinking ages since 1979.
TEEN DRINKING AND "BINGE" DRINKING
Of course, highway fatalities are not the only concern raised about the drinking age. Proponents of the 21 drinking age also claim it reduced teen drinking and "binge" drinking (5+ drinks in an occasion). But that trend, as measured by the Monitoring the Future (MTF) survey, began in 1979, which was several years before most states adopted the 21 law. And raising the drinking age may lead to reduced reporting in surveys even in the absence of actual behavioral change. So all teen surveys ought to be taken with at least a grain of salt, if not a pound.
The province of Ontario (with a drinking age of 19 since 1979) has a similar survey (OSDUS) going back to the 1970s, though not all the measurements are the same. The following table, again courtesy of NHTSA, shows the changes in Ontario during the most relevant time period (1979-1991 unless otherwise stated) compared with the USA. The American data are for grade 12 only, while the Ontario data are for grades 7-13 combined, so they are not directly comparable. The trends, however, are strikingly similar.
Of course, that is only one province. What about the rest of Canada? Unfortunately, most Canadian provinces do not have longitudinal data going back that far, or even before 1996, so we are stuck with doing a crude cross-section using current data for our international comparison. The following table consists of the past-month prevalence of "binge" drinking (5+ drinks in an occasion) for high school seniors as reported in recent surveys, in selected states and provinces. American data were taken from the national Youth Risk Behavior Survey, while Canadian data were taken from various provincial surveys.
We do in fact have a good yardstick for what would have happened had the drinking age not been raised to 21 in the 1980s. It's called Canada. Their drinking ages have remained at 18 or 19, depending on the province, for the past three decades. And it is the country that most resembles America in many ways, especially in terms of its car culture. So let's talk about Canada then.
ALCOHOL-RELATED TRAFFIC FATALITIES
It is often claimed by proponents of the 21 drinking age that raising the drinking age saved lives. While alcohol-related traffic fatalites did decline, correlation does not prove causality. First of all, the trend began in 1982, two years before the National Minimum Drinking Age Act that forced all states to raise their drinking ages to 21 by 1987. Perhaps the trend began even earlier, as total 18-20 year old fatalities began declining in 1979-1980, but 1982 is the first year that FARS has reasonably reliable data for alcohol-related fatalities. And Canada saw a remarkably similar trend, as you can see in the graphs below (courtesy of NHTSA).
Percent Change from 1982-1997 US: drivers age 16-20 in fatal crashes with positive BAC (FARS) Canada: driver fatalities age 16-19 with positive BAC (TIRF) | Percent Change from 1982-1997 US: percentage of drivers age 16-20 in fatal crashes with positive BAC (FARS) Canada: percentage of driver fatalities age 16-19 with positive BAC (TIRF) |
Interestingly, the decline in alcohol-related traffic fatalities since 1982 occurred at about the same rate in both countries, with no evidence of divergence in the expected direction despite the fact that Canada did not raise the drinking age to 21. In both countries, drivers under 21 saw some of the largest declines of all compared with other age groups, though all ages saw some decline over the long run. Moreover, progress continued for Canadian teens from 1997-2005, while unfortunately it stalled for their American counterparts during that time, only resuming after gas prices began to skyrocket (which Americans were not used to) and the economy began to sag. In 2005-2006, the rate of total 15-24 year old traffic fatalities (per 100,000 people) for the USA was 25.5, and 16.9 in Canada, the latter being 33% lower than the former.
In other words, the downward trend in fatalities can be explained entirely by other factors, which likely include, inter alia:
- Tougher laws and penalties for DUI
- Better DUI enforcement
- More education and awareness of the problem of impaired driving
- Designated driver programs
- Seat belt laws
- Safer cars and roads due to improved engineering
- Demographic changes
- Changes in gas prices
Worse still, according to a 2004 book by Leonard Evans, former safety researcher for General Motors, America has been lagging behind several other countries in terms of traffic safety. The table below shows the change in the number and rate of total traffic fatalites (all ages) over time in the US and three other countries that maintained lower drinking ages since 1979.
Country | MLDA | 1979 Fatalities | 2002 Fatalities | % Change (raw) | % Change (per vehicle) | % Change (per VMT) |
USA | 21 | 51,093 | 42,815 | -16.2% | -46.2% | -52% |
UK | 18 | 6,352 | 3,431 | -46.0% | -67.1% | -70% |
Canada | 18 or 19 | 5,863 | 2,936 | -49.9% | -63.5% | N/A |
Australia | 18 | 3,508 | 1,715 | -51.1% | -79.1% | N/A |
TEEN DRINKING AND "BINGE" DRINKING
Of course, highway fatalities are not the only concern raised about the drinking age. Proponents of the 21 drinking age also claim it reduced teen drinking and "binge" drinking (5+ drinks in an occasion). But that trend, as measured by the Monitoring the Future (MTF) survey, began in 1979, which was several years before most states adopted the 21 law. And raising the drinking age may lead to reduced reporting in surveys even in the absence of actual behavioral change. So all teen surveys ought to be taken with at least a grain of salt, if not a pound.
The province of Ontario (with a drinking age of 19 since 1979) has a similar survey (OSDUS) going back to the 1970s, though not all the measurements are the same. The following table, again courtesy of NHTSA, shows the changes in Ontario during the most relevant time period (1979-1991 unless otherwise stated) compared with the USA. The American data are for grade 12 only, while the Ontario data are for grades 7-13 combined, so they are not directly comparable. The trends, however, are strikingly similar.
Drinking Behavior | 1979 | 1991 | % Change, 1979-1991 |
Annual drinking: USA | 88.1% | 77.7% | -12% |
Annual drinking: Ontario | 76.9% | 58.7% | -24% |
Daily drinking: USA | 6.9% | 3.6% | -48% |
Daily drinking: Ontario | 0.9% | 0.4% | -56% |
5 or more drinks: USA (past 2 weeks) | 41.2% | 27.9% | -32% |
5 or more drinks: Ontario (past 4 weeks) | 27.0% | 21.9% | -19% |
5 or more drinks: USA (past 2 weeks, 1979-1993) | 41.2% | 27.5% (1993) | -33% |
5 or more drinks: Ontario (past 4 weeks, grades 7, 9 and 11 only, 1979-1993) | 24% | 15% (1993) | -38% |
Drive after drinking: USA (past 2 weeks) | 31.2% (1984) | 18.7% | -40% |
Drive after drinking: Ontario (annual) | 43.2% (1983) | 20.1% | -53% |
Of course, that is only one province. What about the rest of Canada? Unfortunately, most Canadian provinces do not have longitudinal data going back that far, or even before 1996, so we are stuck with doing a crude cross-section using current data for our international comparison. The following table consists of the past-month prevalence of "binge" drinking (5+ drinks in an occasion) for high school seniors as reported in recent surveys, in selected states and provinces. American data were taken from the national Youth Risk Behavior Survey, while Canadian data were taken from various provincial surveys.
Location | Binge Drinking (Grade 12) | Drove after drinking (Grades 9-12) | MLDA | Year |
USA (overall) | 36.5% | 10.5% | 21 | 2007 |
North Dakota | 47.0% | 18.7% | 21 | 2007 |
South Dakota | 47.3% | 13.0% | 21 | 2007 |
Montana | 46.2% | 18.5% | 21 | 2005 |
Vermont | 38.0% | 9.2% | 21 | 2007 |
Wisconsin | 42.7% | 14.3% | 21 | 2007 |
Alberta | 46% | N/A | 18 | 2005 |
Alberta | 48.5% | 10.3% | 18 | 2008 |
Atlantic Provinces | 49.7% | N/A | 19 | 2007 |
Manitoba | 47% | N/A | 18 | 2007 |
Ontario | 48% | 11.6% | 19 | 2007 |
Saskatchewan | 70%+ | N/A | 19 | 2008 |
Puerto Rico (USA) | 33.2% | 7.3% | 18 | 2005 |
Guam (USA) | 30.3% | 7.8% | 18 | 2007 |
Northern Mariana Islands (USA) | 36.5% | 14.1% | 21 | 2005 |
Care was taken to compare apples to apples, and that is why the YRBS was used for American data instead of the Monitoring the Future survey. Canadian surveys and YRBS report past-month "binge" drinking, while MTF reports it for past two weeks (and thus contains lower numbers). The Manitoba figure was for the past-year, as comparable data for past month were not available, and can thus be considered an upper bound for past-month "binge" drinking.
Note the similarity between the northern states and Canadian provinces which are geographically and demographically similar--they generally tend to be around 50%. There does not appear to be a significant correlation between the drinking age and "binge" drinking rates. Remember again that the American data are more likely underreported than the Canadian data due to the drinking age difference and cultural factors.
Also note the below-average numbers for the US territories of Guam and Puerto Rico, both of which have a drinking age of 18. In fact, even the temperance-oriented Robert Wood Johnson Foundation concedes that Puerto Rico was able to reduce both alcohol-related traffic fatalities and underage (under 18) drinking since the 1990s without raising the drinking age. From 1982 to 2009, Puerto Rico saw a whopping 84% decline in teenage (16-20) drunk driving fatalities, while the nation as a whole saw a 74% drop, in both cases to record-low levels. Now that's a great American success story.
In other words, it appears that Miron and Tetelbaum (2009) were spot on when they said that the drinking age appears to have "only a minor impact on teen drinking," just like they were right about its lack of a lifesaving effect on the highways.
OTHER EFFECTS, OR LACK THEREOF
As for allegedly creating a nation of brain-damaged, alcoholic felons by allowing 18-20 year olds to drink, this myth does not hold water either. In international standardized tests, Canadian 12th graders beat their American counterparts despite the former having similar or lower scores in 4th grade. In fact, nearly all the countries that beat us set the drinking age at 18 or even lower! The alcoholism rates in both the USA and Canada are also roughly equivalent, and the adult per capita alcohol consumption rate is actually slightly lower in Canada. Alcohol-related death rates, both in terms of liver cirrhosis as well as "alcohol use disorder", are also lower in Canada according to the World Health Organization. In fact, Canadians live on average three years longer than Americans. And the rates of violent crimes, especially the most serious ones like homicide, tend to be significantly lower in Canada as well.
In short, puritanical America, with our 21 drinking age, appears to be the less healthy society of the two. And while correlation does not prove causation, the aforementioned statistics certainly won't convince anyone that our illiberal policies are doing much good in reducing alcohol-related problems or improving public health and safety. We need to see the forest for the trees, something America chronically fails to do in terms of alcohol policy.
Perhaps we can learn a thing or two from our neighbor to the north?
QED
2011 UPDATE: Errata have been found (and updated) for some surveys. Also, additional data have been (and will be) added to this post from time to time--stay tuned.
Also note the below-average numbers for the US territories of Guam and Puerto Rico, both of which have a drinking age of 18. In fact, even the temperance-oriented Robert Wood Johnson Foundation concedes that Puerto Rico was able to reduce both alcohol-related traffic fatalities and underage (under 18) drinking since the 1990s without raising the drinking age. From 1982 to 2009, Puerto Rico saw a whopping 84% decline in teenage (16-20) drunk driving fatalities, while the nation as a whole saw a 74% drop, in both cases to record-low levels. Now that's a great American success story.
In other words, it appears that Miron and Tetelbaum (2009) were spot on when they said that the drinking age appears to have "only a minor impact on teen drinking," just like they were right about its lack of a lifesaving effect on the highways.
OTHER EFFECTS, OR LACK THEREOF
As for allegedly creating a nation of brain-damaged, alcoholic felons by allowing 18-20 year olds to drink, this myth does not hold water either. In international standardized tests, Canadian 12th graders beat their American counterparts despite the former having similar or lower scores in 4th grade. In fact, nearly all the countries that beat us set the drinking age at 18 or even lower! The alcoholism rates in both the USA and Canada are also roughly equivalent, and the adult per capita alcohol consumption rate is actually slightly lower in Canada. Alcohol-related death rates, both in terms of liver cirrhosis as well as "alcohol use disorder", are also lower in Canada according to the World Health Organization. In fact, Canadians live on average three years longer than Americans. And the rates of violent crimes, especially the most serious ones like homicide, tend to be significantly lower in Canada as well.
In short, puritanical America, with our 21 drinking age, appears to be the less healthy society of the two. And while correlation does not prove causation, the aforementioned statistics certainly won't convince anyone that our illiberal policies are doing much good in reducing alcohol-related problems or improving public health and safety. We need to see the forest for the trees, something America chronically fails to do in terms of alcohol policy.
Perhaps we can learn a thing or two from our neighbor to the north?
QED
2011 UPDATE: Errata have been found (and updated) for some surveys. Also, additional data have been (and will be) added to this post from time to time--stay tuned.