In an interview with Yahoo News, Gardner said he met with Warren and "a number of senators on both sides of the aisle" on Wednesday to discuss a bill that will prevent the federal government from meddling in state-controlled marijuana industries. He said a draft of the bill could appear as early as later this week.
"Basically, this is a states' rights bill. This is a federalism bill that says if a state like Colorado decides to move forward on medical marijuana, recreational marijuana, CBDs ..., hemp, that that activity is going to be lawfully, legally carried out," Gardner told Yahoo News. CBDs are products derived from a non-psychoactive cannabinoid widely thought to have therapeutic potential.
"If Oklahoma wishes to maintain a prohibition on marijuana, then it would be illegal under state and local law in Oklahoma. But as far as Colorado goes, there would no longer be an illegal activity," Gardner added.
Senator Gardner's office declined to comment, except to confirm what was reported in the Yahoo article. Senator Warren's office also later confirmed the two would be collaborating on the bill.
The proposed bill would not alter the scheduling of the drug. Cannabis is currently schedule 1, or the most tightly regulated, making it as illegal and difficult to study as heroin. Instead the bill "opts the state out of the marijuana provisions" in schedule 1. In other words, a state ignoring marijuana's federal regulation won't be breaking the law.
According to Gardner, Warren got involved in January, when Attorney General Jeff Sessions rescinded the Obama-era Cole Memo, which provided some protections to state marijuana industries. The two had "a number of conversations."
"It was clear that Elizabeth Warren and I were thinking about the same kind of approach on a federalism level," Gardner told Yahoo News.
Gardner said he has no illusions that the bill will pass easily and he anticipates both Democratic and Republican senators may want "tweaks," but he does believe Trump will "hold to his end of the bargain."
Gardner has made headlines in the past year for his obstinate support of Colorado's marijuana industry. After Sessions' move to revoke the Cole Memo, which angered many prominent politicians from marijuana-friendly states, Gardner promised to block all Department of Justice nominations, pending a resolution.
His move prompted Trump to agree earlier this month to support efforts to protect states that have legalized marijuana, ending Gardner's standoff on DOJ nominations.
For her part, Warren has been at the forefront of marijuana politics in her home state of Massachusetts. She has expressed a desire to implement regulation and improve marijuana businesses' access to banking.