HARRISBURG — Pennsylvania's medical marijuana industry finds itself facing a unique and potentially dangerous challenge: the inability to participate in the banking industry.

Because medical marijuana remains illegal under federal law, most banks will not accept accounts or any business at all from purveyors of medical marijuana or those in its ancillary industries.

The situation has resulted in a “cash-and-carry” system of finance, which could prove dangerous for those transporting large amounts of cash from place to place.

It also opens an avenue for unscrupulous purveyors to get around state financial regulations.

The state Department of Banking and Securities, under the direction of Gov. Tom Wolf, has sent a letter to House Speaker Paul Ryan, Senate Majority Leader Mitch McConnell and other congressional leaders to ask for safeguards for the state's banking industry.

“The lack of clarity by the federal government for how banks can serve this industry, without the threat of forfeiture of assets or criminal penalties, results in many transactions occurring in cash,” read the letter from department Secretary Robin Wiessmann.

“Barriers for financial institutions to serve marijuana and ancillary businesses creates a commercial condition lacking robust regulation and supervision and a diminished ability to identify operators acting to circumvent federal and state licensing and regulatory frameworks,” Wiessmann's letter states.

Public safety, tracking funds, loss of economic activity and workforce and community development opportunities are the issues caused by the situation, according to the letter.

“It is incumbent on Congress to resolve the conflict between state cannabis programs and federal statutes that effectively create unnecessary risk for banks seeking to operate in this space without the looming threat of civil actions, forfeiture of assets, reputational risk and criminal penalties,” Wiessmann states.

“We urge Congress to consider legislation that creates a safe harbor for financial institutions to serve a state-compliant business, or entrusts sovereign states with the full oversight and jurisdiction of marijuana-related activity,” the secretary writes.

The letter also is signed by banking officials from 12 other states facing the same issue.

Trent Hartley, the co-founder of Cresco Yeltrah, whose first medical marijuana store opened on Pillow Street in Butler, commended Wolf for his leadership in recognizing the challenges of medical cannabis companies in the inability to use traditional banking systems.

“As more and more states are adding cannabis programs as an alternative to lethal opioids, we are optimistic that Congress will recognize how beneficial this industry is and pass legislation making banking available,” Hartley said in a statement.

Congressman Mike Kelly said in a statement that he could not say how he would vote on a hypothetical piece of legislation without reading and reviewing the bill.

He also shared his stance on medical marijuana.

“I recognize that medical marijuana has had real, verifiable success in alleviating severe suffering for many patients,” Kelly's statement said. “As co-chairman of the Health Care Innovation Caucus, I encourage the medical community to continue researching safe and effective methods of treating chronic pain, which may include the responsible use of medical marijuana by those who are prescribed it.”

Sen. Pat Toomey also sent a statement saying he and his staff are currently “reviewing relevant statutes that apply to financial institutions doing business with these entities and their related tax treatment.”

Regarding his position on medical marijuana, Toomey said it should be available “if there are chemical compounds in marijuana that are proven to be medically useful and helpful.”

Sen. Bob Casey said he reviewed the letter sent by Wiessmann and “is continuing to review legislation that has been proposed in this area.”

Sara Goulet, a spokeswoman for Gov. Wolf, said while federal legislators have confirmed receipt of the letter from Wiessmann, there has been no official response on its content.