PHOENIX (AP) —€” An attorney defending from a court challenge an Arizona citizen’s initiative that would legalize recreational marijuana is calling the attempt to keep the proposal off the ballot a “Hail Mary” effort by opponents of legal pot.

Attorney Kory Langhofer said Tuesday that the lawsuit filed by 13 individuals and groups including Maricopa County Attorney Bill Montgomery and Yavapai County Attorney Sheila Polk is likely to fail because opponents are on thin legal ground.

“I’m very bullish on this lawsuit,” Langhofer said. “The bottom line here is the opponents of this initiative have to make a Hail Mary pass to keep it off the ballot because voters are pretty likely to support this initiative if they ever get a chance to express that.”

Langhofer’s comments came after a Maricopa County Superior Court judge set a schedule for the filing of legal briefs and set an Aug. 12 date to hear oral arguments.

Opponents of the initiative filed by a group called the Campaign to Regulate Marijuana Like Alcohol argue in their lawsuit that the 100-word explanation on petition sheets doesn’t fully explain the effects of the proposed legalization and that it doesn’t contain a legal funding mechanism.

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“This is about the integrity of the initiative process,” Polk said. “And there’s certain constitutional provisions and certain statutes that provide the framework that are focused on making sure voters understand what they are signing and understand what they are ultimately voting on. And if you don’t abide by those rules then you harm the integrity of the process.”

Under the measure, adults age 21 and older could carry up to one ounce of marijuana and consume it privately. Adults could also cultivate up to six marijuana plants in an enclosed space and possess the marijuana produced by the plants. No more than a dozen plants total would be allowed in a single residence.

The system would regulate pot like alcohol, with a 15 percent tax imposed on all retail marijuana sales. Most of the revenue from that tax would go to Arizona schools and education programs.

Polk and other opponent argue that the summary doesn’t adequately explain all the effects of the measure, including its effect on laws regulating driving while impaired. That means the approximately 250,000 people who signed petitions seeking to put the measure on the November ballot weren’t given enough information to understand all its consequences.

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Election officials still are verifying whether the Campaign to Regulate Marijuana Like Alcohol submitted the 150,000 valid signatures needed to qualify for the ballot.

Langhofer calls that argument legally deficient.

“Sheila Polk and company say that the 100-word summary was misleading because it didn’t describe everything in a 30-page initiative. Of course it doesn’t describe everything — it’s a 100 words summarizing 30 pages. And there’s plenty of case law in Arizona that says it doesn’t have to describe everything, it just has to give them a rough idea of what the 30 pages do.”

Polk said she’s worried about the effects of legalizing marijuana.

“I would point you to Colorado that passed a recreation initiative in 2012 and that has just a whole cascade of negative consequences coming from it, including a youth use rate that is now the highest in the nation,” Polk said. “Kids ages 12 to 17 in Colorado now use marijuana on a regular basis that is 74 percent higher than the national average. In the cities and town that allow retail pot shops, they are experiencing increased homelessness that is very significant in terms of tourism.”

Homeless shelters in Denver have reported an increase in people needing services because they moved to Colorado because of legal marijuana. But teen marijuana use rates are actually below the national average, according to a 2015 survey by the state health department. They have remained relatively unchanged since legalization.

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Image by Flickr user Ms. Phoenix