Marijuana plants are seen in Chicago where officers say they discovered two football fields worth of pot plants growing on the city's South Side Wednesday, Oct. 3, 2012. Authorities say more than 1,000 cannabis plants were discovered during a helicopter operation Tuesday. Some were as tall as Christmas Trees. (AP Photo/Teresa Crawford)
The Michigan Supreme Court has heard oral arguments in one of the most significant legal issues since voters approved medical marijuana.
Justices held a hearing Thursday in a case about shops known as dispensaries, where people with medical marijuana cards sell homegrown pot to people who don't grow their own.
The state appeals court last year said there's nothing in the 2008 law that allows it.
The case involves a Mount Pleasant shop that allowed members to sell marijuana to each other.
Isabella County Prosecutor Risa Scully says the medical marijuana act doesn't allow dispensaries where patients can share marijuana with each other.
Dispensary operators lawyer Mary Chartier says the medical marijuana law is silent on dispensaries, so they should be allowed.