DENVER (AP) – Just as Colorado is settling in for a second year of recreational marijuana sales, state lawmakers have some big decisions to make about its older cousin, the medical marijuana market.

The state’s medical-pot regulations are due for automatic renewal in 2015. That means that all the rules about growing, processing and selling medical pot are open to change.

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Colorado’s 2010 marijuana regulations were the template for the rules that now govern the recreational market. But there are some important distinctions between the two, and Colorado’s Legislature will have to consider whether the medical system needs some changes.

The biggest fight will likely be how to squeeze more taxes out of medical pot.

Lawmakers from both parties, along with large for-profit marijuana producers, complain that wide holes in Colorado’s medical marijuana framework have led to a still-thriving unregulated market for pot.

Some caregivers grow large quantities of untaxed pot, with none of the seed-to-sale tracking required of commercial growing operations.

Officials predicted that Colorado’s medical patients would stop paying annual fees for so-called “red cards” and join the recreational market once dispensaries opened to all over 21.

That hasn’t happened, and taxes are the likely culprit. Medical pot is subject only to Colorado’s statewide sales tax, 2.9 percent. That’s about one-tenth of the taxes levied on recreational pot.

The tax differential has helped create a patient base that has grown, not shrunk.

Colorado’s medical marijuana registry has grown from 107,000 people in late 2012 to about 116,000 this year. Pot shops have sold a greater volume of medical marijuana than recreational marijuana products.

“There’s enough of a price differential between recreational and medical to offer people an advantage” to pay $15 a year to stay on the medical registry, said Dr. Larry Wolk, Colorado’s chief medical officer.

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But lawmakers can’t raise medical pot taxes without going back to voters. Instead, they may try to winnow the medical patient pool and drive patients to the recreational market.

One proposal would require more scrutiny of the doctors who recommend marijuana for the most common ailment on the registry – severe pain.

Another likely bill would concern caregivers. The state Department of Regulated Agencies, which reviews expiring regulations, suggested in October that lawmakers require caregivers to register where they’re growing pot.

The agency found that a majority of caregivers now haven’t registered with the Health Department, many of them “because they do not want the government to know of their cultivation.”

But Colorado lawmakers have stumbled for years on efforts to crack down on unregulated marijuana caregivers.

The state constitution guarantees people with certain medical conditions to name a caregiver of their choice, with no mention of taxes.

Patient advocates say to expect push-back on attempts to drive medical patients to the recreational market. “This is nothing more than a money grab,” said Jason Warf, executive director of the Southern Colorado Cannabis Council.

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– By Kristen Wyatt, AP Writer

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