DETROIT (AP) - Legislators on Friday sent Gov. Rick Snyder the first changes in Michigan’s medical-marijuana law in four years, stretching the one-year patient cards to two years and restricting who can grow pot and how it can be transported.

The use of marijuana to alleviate side effects of certain illnesses, such as cancer or chronic pain, was widely endorsed by voters in 2008. Changes have been difficult to make because any amendments to voter-approved laws require 75 percent approval in the Legislature.

State-issued cards given to people who have a doctor’s endorsement for marijuana use would be good for two years instead of one. Caregivers who are allowed to grow marijuana for up to five people would be disqualified if they committed a felony within the past 10 years or if they committed an assault.

More than 130,000 people have marijuana cards in Michigan, and another 25,000 are registered as caregivers. Michael Komorn, an attorney who specializes in medical-marijuana law, said some caregivers are certain to be dropped because of felony convictions.

“That is a terrible one,” Komorn said of the provision. “You may have a father with a felony who may be a caregiver for his wife and grows plants in the basement. Patients develop relationships and now they tell them you need to go somewhere else? It’s a law-enforcement mentality: You have a felony, so you’re a bad person for the rest of your life.”

Messages seeking comment were not immediately returned by key lawmakers Friday. The Legislature met through the night and adjourned before dawn Friday.

Lawmakers backed a bill that would require medical-marijuana users to store their pot in a case in the trunk while riding in a motor vehicle. Marijuana would have to be in a case that’s not easily accessible if the vehicle doesn’t have a trunk. A violation is a misdemeanor.

“It will give police more reasons to search patients’ vehicles. It creates a new crime,” said attorney Matt Abel. “It’s not clear to me what harm they were attempting to eradicate.”

The legislation would also give state regulators the authority to hire contractors to process the $100 medical-marijuana cards, although the Department of Community Health in 2010 found that going to a private business probably wouldn’t save money.

The medical-marijuana program has been running a surplus estimated at $16.7 million as of Sept. 30, according to the Senate Fiscal Agency.

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