Attitudes in Washington may be shifting in favor of easing marijuana restrictions as health and business benefits become more apparent, but there are still major legislative obstacles ahead.

Three bills that have been introduced to U.S. Congress this year—two with bipartisan support—would pave the way for a more accepting federal environment for cannabis.

“With so many libertarian Republicans and states-rights conservatives, there has been more support from Republicans,” Dan Riffle, director of federal policies for the Marijuana Policy Project said. “…They’re in favor of letting states set their own polices.”

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There are currently 23 states that have legalized marijuana for medical purposes, and four plus Washington D.C. that have also approved it for recreational use. But the continued federal ban on the substance has hampered the development of the industry, to the frustration of investors and entrepreneurs.

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The Compassionate Access, Research Expansion, and Respect States, or CARERS, Act was introduced in March by Democratic Sen. Cory Booker of New Jersey. If passed, the law would exclude persons acting within state law on the use or sale of marijuana from the federal Controlled Substances Act, transfer cannabis from schedule I classification to schedule II and separate cannabidiol from the definition of marijuana.

Co-sponsors to the bill include Republican Sens. Rand Paul of Kentucky and Dean Heller of Nevada.

“ “The clinical potential of cannabinoid-related compounds is simply undeniable at this point,” Dr. Yankel Gabet, Tel Aviv University ”

Cannabidiol, commonly referred to as CBD, is a non-psychoactive cannabinoid found in marijuana plants that has been examined for medical purposes. CBD has been used to treat epilepsy, but its status as a schedule I drug has made research and administration difficult.

If a substance is classified as schedule I, it is deemed to have no accepted medical use, is not safe for medical use under supervision—like hospital administration—and has a high potential for abuse. Other drugs classified as schedule I include heroin, LSD and Ecstasy.

“This movement is coming from patients and parents of kids with seizure disorders,” Riffle said. “They’re saying let’s stop treating this as a criminal justice issue and start treating it as a medical health issue.”

CBD has also been proven to help heal bone fractures, according to a study published in The Journal of Bone and Mineral Research.

“The clinical potential of cannabinoid-related compounds is simply undeniable at this point,” Dr. Yankel Gabet, one of the study’s researchers, said in a news release.

Though Republican Sen. Chuck Grassley of Iowa, who sits on the Senate Judiciary Committee, has been a vocal opponent of marijuana legalization, he said in a June Senate hearing that he recognized the need to research potential health benefits of CBD.

“Even though all the leading medical organizations reject the idea of smoked marijuana as medicine, many of them have called for further research into the potential medical use of CBD,” Grassley said in a statement on the hearing.

While the exclusion of CBD from marijuana’s schedule classification would aid research, the transition of cannabis to schedule II would do little to improve the status of the drug federally.

“It would go from being classified as heroin to being classified as cocaine,” Taylor West, deputy director of the National Cannabis Industry Association, said. “It needs to move to schedule III or be taken off, those are much more dramatic moves in keeping with the idea that states should be able to handle issues in the way they choose.”

The CARERS Act includes a provision that would protect banks that are lending to state legalized cannabis business from federal law. A similar call for banking safety is laid out in a stand-alone bill introduced in April.

The Marijuana Businesses Access to Banking Act was introduced by Democratic Rep. Ed Perlmutter of Colorado and would exempt cannabis businesses in states where it has been legalized from federal banking regulations.

Republican Rep. Mike Coffman of Colorado is a co-sponsor of the bill.

Currently, depository institutions can refuse services to marijuana retail businesses for fear of federal retribution.

“Banking is the issue that has the most momentum,” Riffle said. “The banking issue is part of the broader issue of state and federal laws.”

In February, Democratic Rep. Earl Blumenauer of Oregon introduced the Marijuana Tax Revenue Act, allowing legal marijuana businesses to make the same tax deductions as other federally recognized businesses.

The bill would counteract Section 280E of the U.S. tax code, which prohibits tax deductions or credits for businesses trafficking in controlled substances—specifically those classified as schedule I or schedule II.

Under this code, marijuana businesses must, in effect, pay taxes on their gross revenue instead of net revenue because they are unable to make standard deductions.

“The point of these [state] laws is to take marijuana out of the black market, and it’s harder to take it out of the black market when businesses are taxed so heavily,” Riffle said.

West added, “It’s not a tax break, just tax us like everybody else.”

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While the introduction of these bills may indicate a growing legislative acceptance of marijuana, they are facing a Congress that has become increasingly unproductive.

“It is unlikely we’re going to see any stand-alone legislation move through this Congress,” said Paul Armentano, deputy director of National Organization for the Reform of Marijuana Laws. “It’s not an indictment of the legislation, but an acknowledgment of adversarial parties in Congress who reach very little compromise.”

Armentano added that it has been more likely for marijuana legislation to pass as amendments to existing laws rather than stand-alone bills. Despite changing popular opinion of marijuana legalization, Congress has been hesitant to make any federal changes.

“This was public policy created by Congress, it is a public policy problem created by Congress’s own doing, and, ultimately, it is Congress’s responsibility to fix it,” Armentano said.