Tieszen said he does not want to create a system where people get advance permission to use marijuana for medical purposes and then buy it from licensed shops. The bill merely offers critically ill people a possible defense in court if marijuana helps them deal with pain or nausea, he said.
Tieszen said he does not know of any other state that has a similar law.
Bryan Gortmaker, director of the state Division of Criminal Investigation, said selling marijuana would still be illegal if the bill passes. Allowing a medical defense in possession cases would attract dealers to South Dakota, he said.
"It's going to encourage the distribution of marijuana in our state," Gortmaker said. "If marijuana usage is encouraged in South Dakota, the profiteers, those looking to make money off this, will come with it."
Minnehaha County States Attorney Aaron McGowan said the measure would clog up the courts with hearings and jury trials on misdemeanor possession charges because many people would argue they need the marijuana for medical treatment.
"It will be burdensome to the taxpayer," McGowan said.
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