Study shows medical marijuana laws reduce traffic deaths

A groundbreaking new study shows that laws legalizing medical marijuana have resulted in a nearly nine percent drop in traffic deaths and a five percent reduction in beer sales.

"Our research suggests that the legalization of medical marijuana reduces through reducing by ," said Daniel Rees, professor of economics at the University of Colorado Denver who co-authored the study with D. Mark Anderson, assistant professor of economics at Montana State University.

The researchers collected data from a variety of sources including the National Survey on Drug Use and Health, the Surveillance System, and the .

The study is the first to examine the relationship between the legalization of medical marijuana and .

"We were astounded by how little is known about the effects of legalizing medical marijuana," Rees said. "We looked into traffic fatalities because there is good data, and the data allow us to test whether was a factor."

Anderson noted that traffic deaths are significant from a policy standpoint.

"Traffic fatalities are an important outcome from a policy perspective because they represent the leading cause of death among Americans ages five to 34," he said.

The economists analyzed traffic fatalities nationwide, including the 13 states that legalized medical marijuana between 1990 and 2009. In those states, they found evidence that alcohol consumption by 20- through 29-year-olds went down, resulting in fewer deaths on the road.

The economists noted that simulator studies conducted by previous researchers suggest that drivers under the influence of alcohol tend to underestimate how badly their skills are impaired. They drive faster and take more risks. In contrast, these studies show that drivers under the influence of marijuana tend to avoid risks. However, Rees and Anderson cautioned that legalization of medical marijuana may result in fewer traffic deaths because it's typically used in private, while alcohol is often consumed at bars and restaurants.

"I think this is a very timely study given all the medical marijuana laws being passed or under consideration," Anderson said. "These policies have not been research-based thus far and our research shows some of the social effects of these laws. Our results suggest a direct link between marijuana and alcohol consumption."

The study also examined marijuana use in three states that legalized medical marijuana in the mid-2000s, Montana, Rhode Island, and Vermont. Marijuana use by adults increased after legalization in Montana and Rhode Island, but not in Vermont. There was no evidence that marijuana use by minors increased.

Opponents of medical marijuana believe that legalization leads to increased use of marijuana by minors.

According to Rees and Anderson, the majority of registered medical marijuana patients in Arizona and Colorado are male. In Arizona, 75 percent of registered patients are male; in Colorado, 68 percent are male. Many are under the age of 40. For instance, 48 percent of registered patients in Montana are under 40.

"Although we make no policy recommendations, it certainly appears as though laws are making our highways safer," Rees said.

More information: The study is entitled, "Medical Marijuana Laws, Traffic Fatalities, and Alcohol Consumption." It can be found at: www.iza.org/en/webcontent/pers… /index_html?key=4915

Provided by University of Colorado Denver

4.7 /5 (41 votes)

Related Stories

Marijuana use may double the risk of accidents for drivers

Oct 06, 2011

Over 10 million people age 12 or older are estimated to have driven under the influence of illicit drugs in the prior year, according to a 2009 National Survey on Drug Use and Health. While marijuana is the most commonly ...

US capital okays medical marijuana

May 04, 2010

City councillors in Washington voted unanimously on Tuesday to allow the US capital to join 14 states in allowing medical marijuana to be used to treat certain chronically ill patients.

Recommended for you

Study examines effect of hospital switch to for-profit status

12 hours ago

Hospital conversion from nonprofit to for-profit status in the 2000s was associated with better subsequent financial health but had no relationship to the quality of care delivered, mortality rates, or the proportion of poor ...

Hospital acquisitions leading to increased patient costs

12 hours ago

The trend of hospitals consolidating medical groups and physician practices in an effort to improve the coordination of patient care is backfiring and increasing the cost of patient care, according to a new study led by the ...

User comments

Adjust slider to filter visible comments by rank

Display comments: newest first

PS3
4.5 / 5 (10) Nov 29, 2011
Free the weed!
Eric_B
4.5 / 5 (13) Nov 29, 2011
also, pot smokers would rather stay home, order pizza in, watch tv and just have sex.

alkys; drive crazy, crash into things, get into fights, rape, puke all over etc,etc,etc...
Temple
4.6 / 5 (14) Nov 29, 2011
It's a substance that can be grown very cheaply by anybody.

The currently legal drugs (tobacco, alcohol, pharmaceuticals) and the current enforcement/penal system, have way too much vested interest, yield way too much lobbying power, and donate *far* too much in campaign funding to ever allow the end of Prohibition.
Shootist
4.2 / 5 (10) Nov 29, 2011
A groundbreaking new study shows that laws legalizing medical marijuana have resulted in a nearly nine percent drop in traffic deaths and a five percent reduction in beer sales.


I'm sure the politicians in Washington will be hearing loud and long from Miller Brewing, et. al.
axemaster
4.3 / 5 (6) Nov 29, 2011
resulted in a nearly nine percent drop in traffic deaths

Wow! This is really remarkable if true. That's a huge reduction!
Alex_
4.1 / 5 (7) Nov 29, 2011
Prohibition Will never end, even if al the science and statistics suggests it.
Our government have to many vested interest in Jails. taxable non producable goods and the stigma or marijuana is already to strong for the cliche to ever die.
but one can still dream
waste of tax payer money.
Beard
3.7 / 5 (3) Nov 30, 2011
Prohibition Will never end, even if al the science and statistics suggests it.
Our government have to many vested interest in Jails. taxable non producable goods and the stigma or marijuana is already to strong for the cliche to ever die.
but one can still dream
waste of tax payer money.


It's not the same everywhere. I wouldn't be surprised if Canada or countries in Europe decide to legalize it in the next decade.
Nerdyguy
1.2 / 5 (11) Nov 30, 2011
Extremely misleading. Shame on PhysOrg for piss-poor reporting.

This study was funded by the German Institute for the Study of Labor. No mention of that here.

It drew several conclusions and stated things quite differently from the summary and headline here. No mention of that either.

It was a review of a mish-mash of raw data by two economists.

Even the two economists go out of their way to hedge their bets in the paper, stating repeatedly that these were just simple statistical correlations and could be due to "other factors" than those they have hypothesized.

Did anyone really think they were drawing good scientific conclusions by looking at traffic accidents, medical marijuana laws (which presumably don't affect the target of the study in any way unless a teen has cancer, etc.), and traffic fatalities?

What a heaping pile of crap.

The only part I can't figure out is the German's motivation. And they literally make no reference to it in the paper.
Deves
not rated yet Dec 01, 2011
Extremely misleading.


Don't hate the player....



Did anyone really think they were drawing good scientific conclusions by ...


Like it was tradition to use scientific conclusions when talking / making actions about marijuana?
antonima
not rated yet Dec 01, 2011
I'm sure that anyone who does scientific studies about marijuana doesn't hold biases ;)

Still, pot is not a harmful substance, and the prohibition is just about 'mentally disabled' . . . though it does drive prices up.
NotAsleep
not rated yet Dec 02, 2011
NerdyGuy, I could be wrong but I think they only used IZA (the German Institute for the Study of Labor) as a large-scale publisher of their work. The study was clearly not aimed at changing any policy but was attempting to bring more attention to the issue. The author is correct in stating that very little data exists on the social implications of legalizing pot in the US...
rwinners
5 / 5 (1) Dec 05, 2011
@nerdy.... even cops know that marijuana and even more powerful drugs should be decriminalized. It is a patent waste of taxpayer resources to enforce laws criminalize private behavior that does not injure another.
It is far cheaper for society to attend to the addicts than to just lock them away for x number of years.
Do get out from behind that computer and talk to real people once in a while.
Nerdyguy
1 / 5 (2) Dec 05, 2011
@nerdy.... even cops know that marijuana and even more powerful drugs should be decriminalized. It is a patent waste of taxpayer resources to enforce laws criminalize private behavior that does not injure another.
It is far cheaper for society to attend to the addicts than to just lock them away for x number of years.
Do get out from behind that computer and talk to real people once in a while.


Pretty funny stuff. Why are you telling me this?