The ruling comes after Maricopa County essentially banned dispensaries on the grounds that they were federally illegal. Judge Michael Gordon called the law changes "a transparent attempt to prevent implementation of the Arizona Medical Marijuana Act".
Gordon said the counties have a right to ban illegal activities, but since medical cannabis is allowed by Arizona law the county commissioners can't use their powers to supersede the rights of dispensaries to operate.
Maricopa County Attorney Bill Montgomery disagrees. He's argued for some time now that the county cannot actively allow people to violate federal law (even though their sheriff does it all the time). Montgomery has now twice tried to ban dispensaries through county zoning rules.
Gordon cited the fact that more than one-third of all states have allowed medical cannabis and the federal government has not sued to shut down any of those programs. He also says that state law expressly allows dispensaries to operate.
"This court will not rule that Arizona, having sided with the ever-growing minority of states and having limited it to medical use, has violated public policy," Gordon wrote in his decision.
Montgomery, predictably, has appealed the ruling and has ordered the Maricopa County board of supervisors to craft new zoning laws that ban dispensaries in any unincorporated areas of the county.
Arizona medical marijuana patients are allowed to cultivate their own cannabis so long as they live more than 25 miles from the nearest dispensary. Patients are allowed to purchase 2.5 ounces from dispensaries every two weeks.