COLUMBIA - When a push for a marijuana-related bill succeeded last year, proponents considered it a huge coup for an issue some thought could get blocked by more conservative members of the Republican-controlled S.C. Legislature.

But the bill, which legalizes a marijuana-derived product called CBD oil that treats severe epilepsy, remains tangled. Policy-makers must confront how to get patients access to the drug when doing so remains illegal under federal law.

That's why Sen. Tom Davis, R-Beaufort, and Rep. Jenny Horne, R-Charleston, are co-chairs of a committee that begins to meet Wednesday. It plans to find ways to make the bill a reality and perhaps advocate for broader legislation that would allow more patients to access marijuana.

State police, the Department of Agriculture, the Department of Health and Environmental Control and the Medical University of South Carolina among others all have representatives on the panel in order to get broad sign-off for how marijuana-related products can be grown, distributed, prescribed and sold, Davis said.

"We need to go ahead and provide the rules of the game," said Davis, who spearheaded the CBD effort with Horne in the last legislative session.

One of the biggest issues is that bringing in marijuana across state lines remains illegal. While Congress has not changed the law, the federal government has chosen not to enforce it in the states that have chosen to legalize medical or recreational marijuana. The CBD oil treatment has gained national prominence because of ongoing experiments in Colorado, where medical and recreational use of the drug is legal.

"If we're going to have a meaningful program in South Carolina, we have to figure out a way to produce it in our state," Horne said.

One possible part of the solution is to open up marijuana use for all medical benefits, something that is expected to be a part of the discussion. "We want it to be controlled and certainly regulated," Horne said.

The committee also includes Sen. Brad Hutto, D-Orangeburg, a U.S. Senate candidate, and Rep. David Weeks, D-Sumter.

Jill Swing, the mother of 6-year-old Mary Louise Swing, who has severe epilepsy, was a constant presence in the Statehouse as she pushed for the passage of the CBD oil bill this year. She said that while the bill legalizes the oil, there is no way for her daughter to get access to the treatment because no one can distribute it in South Carolina. She believes the oil could help alleviate her daughter's symptoms.

"We certainly made some headway, but we've still got work to do to gain access," Swing said. She also hopes that the panel - which is still developing its full agenda - will discuss ways to help more sick children obtain access to marijuana.

"I always felt like if someone has a child with cancer, their child has every right as mine (to access marijuana)," she said.

Davis said he hopes to use the panel to hold hearings to build public support for the issue.

"It doesn't make any sense to me that we should limit the relief to patients ... when there is a plant that might provide better relief," he said. The committee hopes to deliver its solutions for the best way forward by mid-January.

Reach Jeremy Borden at 708-5837.