DENVER (AP) – Colorado’s governor signed into law a crackdown on medical marijuana Monday, one of two measures designed to ferret out people improperly using and selling untaxed marijuana.

The law limits caregivers, those who grow pot on behalf of patients, to 99 plants. The change means that some high-volume caregivers will face the same oversight as commercial growers, paying licensing fees and undergoing background checks.

The new rules have support from the recreational pot industry, which has complained that light regulation on Colorado’s caregivers has invited black-market growers who don’t face residency requirements, background checks or commercial “seed-to-sale” tracking used to ensure pot plants are grown and sold legally.

“We’re really trying to make sure that caregivers are part of our regulatory system,” said Rep. Jonathan Singer, D-Longmont, who sponsored the bill.

Caregivers have successfully resisted such limits for years, but the law includes some concessions that won their acceptance.

For example, the law eliminates an unenforced requirement that parents of marijuana patients under 18 grow the drug. That rule had put some parents who moved to Colorado seeking cannabis treatments for their children outside the law.

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It also sets up a task force to start work on public access to the state’s few marijuana testing labs. The marijuana industry has generally opposed public access to the labs, fearing backlogs.

Finally, the law allows school districts to consider allowing medical marijuana use on campus, as long as the pot is administered by a parent or designated medical professional, not a school nurse. The pot-in-schools allowance would be the nation’s first, though it’s not clear how many school districts would participate.

Gov. John Hickenlooper said the law was a compromise worked out by both political parties, the pot industry and caregivers.

“It is a pretty good reflection of what the community wants,” Hickenlooper said.

The law doesn’t require caregivers to register their growing operations. Instead, it encourages them to register by assuring them that authorities could verify their number of plants without starting a criminal investigation, instead of forcing caregivers to prove in court that their operations are legal.

Hickenlooper signed the measure at a Denver police station to show goodwill between law enforcement and caregivers. The language in the law came after years of testy negotiations between medical marijuana groups and police.

“There are good reasons for all sides to not trust each other,” said Teri Robnett, head of the Cannabis Patients Alliance who helped negotiate the language.

The governor has yet to sign the other medical marijuana law. That measure updates marijuana regulations that were written before Colorado made pot legal for adults in 2012.

LINK: Senate Bill 14

– By Kristen Wyatt, AP Writer

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