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# Teens Don't Smoke More Pot After Medical Marijuana Laws Passed, Study Finds

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## Video: Inside the World of Medical Marijuana for Kids

[Watch (HLS stream): Inside the World of Medical Marijuana for Kids](https://cdn.jwplayer.com/manifests/6Ic4KUCK.m3u8) (16:16)

![Inside the World of Medical Marijuana for Kids](https://cdn.jwplayer.com/v2/media/6Ic4KUCK/poster.jpg?width=720)

_Published 2014-10-21. The story of a family's illegal cross-country drive to transport marijuana oil for their epileptic 3-year-old daughter. A look inside the quasi-legal, science free world of medical marijuana for children from TIME's Red Border Films_


![Dan Kedmey](https://static.time.com/v3/assets/bltea6093859af6183b/blt1fcb9e8a614ad0c9/6986a6b3d0b6f22eb2306735/dan-kedmey-time.jpg?branch=production&width=3840&quality=75&auto=webp&crop=1:1)

by 

[Dan Kedmey](https://time.com/author/dan-kedmey/)


![Dan Kedmey](https://static.time.com/v3/assets/bltea6093859af6183b/blt1fcb9e8a614ad0c9/6986a6b3d0b6f22eb2306735/dan-kedmey-time.jpg?branch=production&width=96&quality=75&auto=webp)

## Dan Kedmey


Jun 16, 2015 1:19 PM UTC

![An Initiative To Legalize Marijuana In California To Appear On Nov. Ballot](https://static.time.com/v3/assets/bltea6093859af6183b/bltc63750e86747acf2/698854bae53aba30464de317/gettyimages-98049962.jpg?branch=production&width=3840&quality=75&auto=webp&crop=3:2)

One-ounce bags of medicinal marijuana are displayed at the Berkeley Patients Group March 25, 2010 in Berkeley, California.

One-ounce bags of medicinal marijuana are displayed at the Berkeley Patients Group March 25, 2010 in Berkeley, California.Justin Sullivan—Getty Images

![Dan Kedmey](https://static.time.com/v3/assets/bltea6093859af6183b/blt1fcb9e8a614ad0c9/6986a6b3d0b6f22eb2306735/dan-kedmey-time.jpg?branch=production&width=3840&quality=75&auto=webp&crop=1:1)

by 

[Dan Kedmey](https://time.com/author/dan-kedmey/)


![Dan Kedmey](https://static.time.com/v3/assets/bltea6093859af6183b/blt1fcb9e8a614ad0c9/6986a6b3d0b6f22eb2306735/dan-kedmey-time.jpg?branch=production&width=96&quality=75&auto=webp)

## Dan Kedmey


Jun 16, 2015 1:19 PM UTC

New research has cast serious doubts on the argument that legalization of medical marijuana would lead to more widespread use among teenagers.

The study, which was published Tuesday by Columbia University researchers in the _The Lancet Psychiatry,_ examined marijuana use among more than a million teenagers over 24 years.

The researchers found no discernible impact in the 21 states that had legalized the drug for medical use. “The risk of marijuana use in states before passing medical marijuana laws did not differ significantly from the risk after medical marijuana laws were passed,” the co-authors [wrote](http://press.thelancet.com/AdolescentMarijuana.pdf).

While researchers observed no discernible change after the laws were passed, they did find drug use rates were generally higher in states that had legalized marijuana. “State-level risk factors other than medical marijuana laws could contribute to both marijuana use and the passage of medical marijuana laws, and such factors warrant investigation,” the authors [concluded](http://press.thelancet.com/AdolescentMarijuana.pdf).

### Go Inside the Harvest of Colorado's Most Controversial Marijuana Strain

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/blt996485eeb7d40173/6986a6f0e53aba915f4d4c41/charlottes-web-pot-weed-farm-colorado-1.jpg?branch=production&width=3840&quality=75&auto=webp)

Charlotte's Web grows on the Stanley brother's farm near Wray, Colo. on Sept. 22, 2014\. The Stanley Brothers have developed a popular strain of cannabis that has been found to be helpful in reducing seizures in some children. Charlotte's Web is high in a compound called cannabidiol (CBD) and low in tetrahydrocannabinol (THC) the compound that causes a high. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/blt46da2c8281d5106d/6986a6f006f2c103d3331172/charlottes-web-pot-weed-farm-colorado-2.jpg?branch=production&width=3840&quality=75&auto=webp)

Charlotte's Web grows on the Stanley brother's farm near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/bltba17525c5d9e77c6/6986a6f1cd68488a9d096d0d/charlottes-web-pot-weed-farm-colorado-3.jpg?branch=production&width=3840&quality=75&auto=webp)

From left: Zachary Sobol, Michael Atchley, and Jared Stanley walk to the farm to prepare for harvest of Charlotte's Web near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/blt6cda38d1be484643/6986a6f1810bbb5633c93c6e/charlottes-web-pot-weed-farm-colorado-4.jpg?branch=production&width=3840&quality=75&auto=webp)

Rows of Charlotte's Web await harvest at the Stanley brother's farm near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME


![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/bltff67be1b6777c8f9/6986a6f2d0b6f235133067a5/charlottes-web-pot-weed-farm-colorado-5.jpg?branch=production&width=3840&quality=75&auto=webp)

Jared Stanley helps in the harvest of Charlotte's Web on the Stanley brother's farm near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/blt024c867bb25945c4/6986a6f206f2c1f97a331176/charlottes-web-pot-weed-farm-colorado-6.jpg?branch=production&width=3840&quality=75&auto=webp)

Colin Sparks searches for seeds during the harvest of Charlotte's Web on the Stanley brother's Charlotte's Web farm near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/blt81f2b8456857bbb2/6986a6f2169ab0d98127b8f9/charlottes-web-pot-weed-farm-colorado-7.jpg?branch=production&width=3840&quality=75&auto=webp)

Discarded leaves of Charlotte's Web at a farm near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME


![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/bltc4560baa6474fe5a/6986a6f3cd804db3a9ccd24b/charlottes-web-pot-weed-farm-colorado-8.jpg?branch=production&width=3840&quality=75&auto=webp)

Tim Knight helps in the harvest of Charlotte's Web on the Stanley brother's farm near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/bltb8270a5644d2f552/6986a6f355a859287da82fc7/charlottes-web-pot-weed-farm-colorado-9.jpg?branch=production&width=3840&quality=75&auto=webp)

Rows of Charlotte's Web await travel to a drying facility after being harvested on a farm near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/bltd21d20fbfa742f96/6986a6f3f983e73de0050087/charlottes-web-pot-weed-farm-colorado-10.jpg?branch=production&width=3840&quality=75&auto=webp)

Zachary Sobol catches a ride on a trailer to the Stanley brother's farm during harvest of Charlotte's Web near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME


![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/blt06654b573df6e1d9/6986a6f5810bbbe553c93c76/charlottes-web-pot-weed-farm-colorado-11.jpg?branch=production&width=3840&quality=75&auto=webp)

Rows of Charlotte's Web await travel to a drying facility after being harvested from a farm near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/blt995ff264b357e64f/6986a6f5cd6848ed4e096d16/charlottes-web-pot-weed-farm-colorado-12.jpg?branch=production&width=3840&quality=75&auto=webp)

One of the Stanley brother's greenhouses growing cannabis near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/blt865a8c85a6102b8a/6986a6f53617606cc890e3ab/charlottes-web-pot-weed-farm-colorado-13.jpg?branch=production&width=3840&quality=75&auto=webp)

Zachary Sobol hangs rows of Charlotte's Web to dry after harvest in Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME


![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/blt37622e3d537ecede/6986a6f6d0b6f26d773067b4/charlottes-web-pot-weed-farm-colorado-14.jpg?branch=production&width=3840&quality=75&auto=webp)

Penn Mattison, left, and Zachary Sobol, right, hang rows of Charlotte's Web to dry after being harvested from a farm near Wray, Colo. on Sept. 22, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/bltb34ae4c07b7422cf/6986a6f5e53aba25e04d4c51/charlottes-web-pot-weed-farm-colorado-15.jpg?branch=production&width=3840&quality=75&auto=webp)

The Stanley brothers' new company laboratory in Boulder, Colo. on Sept. 23, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/bltb7aae125134b7a40/6986a6f6d0b6f2620b3067b0/charlottes-web-pot-weed-farm-colorado-16.jpg?branch=production&width=3840&quality=75&auto=webp)

A petri dish full of cannabis explants await transfer and transplanting at the Stanley brothers' lab in Boulder, Colo. on Sept. 23, 2014. Matt Nager for TIME


![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/bltd9e2a0e5dbf9e44d/6986a6f6169ab05fda27b8fd/charlottes-web-pot-weed-farm-colorado-17.jpg?branch=production&width=3840&quality=75&auto=webp)

Molecular plant biologist and lab manager Bear Reel awaits the cooling of agar to help induce rooting of transplanted cannabis plants at the Stanley brothers' company laboratory in Boulder, Colo. on Sept. 23, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/blt09656b0d48d699d1/6986a6f7e8524b3a5960516e/charlottes-web-pot-weed-farm-colorado-18.jpg?branch=production&width=3840&quality=75&auto=webp)

The lab notebook of molecular plant biologist and lab manager Bear Reel at the Stanley brothers' company laboratory in Boulder, Colo. on Sept. 23, 2014. Matt Nager for TIME

![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/blt767058e2af626a3f/6986a6f7d0b6f267cd3067b8/charlottes-web-pot-weed-farm-colorado-19.jpg?branch=production&width=3840&quality=75&auto=webp)

A flask of agar cools before explants of hemp are transplanted to help induce rooting and new growth at the Stanley brothers' company laboratory in in Boulder, Colo. on Sept. 23, 2014. Matt Nager for TIME


![Charlotte's Web Stanley Brothers Pot Weed Marijuana Colorado California](https://static.time.com/v3/assets/bltea6093859af6183b/bltf3d827ffa0dc5265/6986a6f713c79f3c541943a6/charlottes-web-pot-weed-farm-colorado-20.jpg?branch=production&width=3840&quality=75&auto=webp)

Tissue cutter technician Meg Regan holds a vial of explants before sanitizing and transplanting at the Stanley brothers' laboratory in Boulder, Colo. on Sept. 23, 2014. Matt Nager for TIME

Legalized Pot Does Not Lead to Wider Use Among Teens, Study Finds

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