Medical Marijuana

FILE - This July 1, 2011 file photo shows fake marijuana displayed in a case, at The 2811 Club, a private cannabis club that plans to dispense marijuana to medically qualified patients in Phoenix.  (AP Photo/Ross D. Franklin, File)

Medical Marijuana

FILE - This July 1, 2011 file photo shows fake marijuana displayed in a case, at The 2811 Club, a private cannabis club that plans to dispense marijuana to medically qualified patients in Phoenix.  (AP Photo/Ross D. Franklin, File)

Medical marijuana

While holding up their medical marijuana cards, Dennis Cox, left, and Mike Gonzalez, right, wait as the first two people in line prior to the opening at Arizona Organix, the first legal medical marijuana dispensary to open in Arizona, Thursday Dec. 6, 2012, in Glendale, Ariz. Several dozen waited outside for the Glendale dispensary to open, the first among 96 applicants chosen through a lottery system for 126 geographic areas across the state.(AP Photo/Ross D. Franklin)

Medical marijuana

Medical Marijuana

Medical marijuana

Medical marijuana

Medical marijuana

Medical marijuana

Medical marijuana

Medical marijuana

Medical marijuana

Medical marijuana

Medical marijuana

Medical marijuana

Medical marijuana

Marijuana

A marijuana plant is seen growing at Med Grow Cannabis College in Southfield, Mich., Tuesday, Dec. 14, 2010. Michigan's two-year-old law allowing the use of marijuana for medical purposes is leaving communities, courts, patients and police locked in disputes over what is legal and what isn’t. (AP Photo/Carlos Osorio)

Marijuana

A marijuana plant is seen growing at Med Grow Cannabis College in Southfield, Mich., Tuesday, Dec. 14, 2010. Michigan's two-year-old law allowing the use of marijuana for medical purposes is leaving communities, courts, patients and police locked in disputes over what is legal and what isn’t. (AP Photo/Carlos Osorio)

Marijuana

A marijuana plant is seen growing at Med Grow Cannabis College in Southfield, Mich., Tuesday, Dec. 14, 2010. Michigan's two-year-old law allowing the use of marijuana for medical purposes is leaving communities, courts, patients and police locked in disputes over what is legal and what isn’t. (AP Photo/Carlos Osorio)

Marijuana

A marijuana plant is seen growing at Med Grow Cannabis College in Southfield, Mich., Tuesday, Dec. 14, 2010. Michigan's two-year-old law allowing the use of marijuana for medical purposes is leaving communities, courts, patients and police locked in disputes over what is legal and what isn’t. (AP Photo/Carlos Osorio)

Medical Marijuana Testing Laboratory

Steve Cottrell founded AZ Med Testing, a medical marijuana testing laboratory in Tempe, after Arizona voters approved the medicinal use of the drug in 2010. [Julia Shumway/Cronkite News]

Medical marijuana lottery

State health department auditors Connie Phillips and Kurt Schulte time the ping pong balls in the Atom Action Bubble Top Bingo Blower used Tuesday to select who gets to operate marijuana dispensaries around the state. The drawing went ahead despite threats by Attorney General Tom Horne to seek a court ruling that the shops are illegal. (Capitol Media Services photo by Howard Fischer)

Medical marijuana lottery

FILE PHOTO -- State health department auditors Connie Phillips and Kurt Schulte time the ping pong balls in the Atom Action Bubble Top Bingo Blower used to select who gets to operate marijuana dispensaries around the state. (Capitol Media Services photo by Howard Fischer)