The chief Senate sponsor of a proposal to legalize medical marijuana in Minnesota says a House alternative "falls short in a number of ways," but he hopes the two plans can be reconciled and a final bill passed this session.

Sen. Scott Dibble, DFL-Minneapolis, wrote in a letter to Gov. Mark Dayton and Rep. Carly Melin, the House sponsor, that he's pleased the House voted in favor of medical marijuana. The House approved its bill Friday, approving a limited distribution system that would make the drug available to significantly fewer patients than its Senate counterpart. Dayton said after Friday's vote that he could sign the House's measure but not the Senate's.

But Dibble says it's wrong to call the Senate proposal more expansive or broad than the House plan. Dibble notes the Senate proposal had much more thorough vetting and underwent a number of revisions during the Senate's committee process.

While law enforcement groups oppose the Senate bill, Dibble says it includes more provisions to punish medical marijuana patients who divert the drug for recreational use. Dibble also criticizes the provision of the House that bars use of marijuana in its whole plant form, allowing only pill or oil forms of cannabis. Dibble says pill or oil cannabis is typically much more potent than in marijuana in plant form, and often does not provide an immediate benefit.

Neither the House nor Senate bills allow smoking marijuana, but the Senate allows the whole plant to be vaporized and inhaled.

The House proposal authorizes only one site for growing marijuana, with two additional distribution sites. The Senate proposal would allow 55 grow-and-distribute sites. Dibble is offering to cut that number to 24 sites, or three in each of the state's eight congressional districts. He says one manufacturing site for the whole state presents a number of logistical problems, and that only three distribution sites would mean some patients could have to drive many hours to obtain medical marijuana.

Dibble's criticisms of the House proposal suggest a House-Senate conference committee on the medical marijuana bill is likely. "I am convinced a middle ground exists between the House and the Senate files," Dibble wrote in his letter to Dayton and Melin.