With marijuana use, either medicinal or recreational, already legal in 29 states, a bipartisan team of U.S. senators is urging the Treasury Department’s Financial Crimes Enforcement Network to take further action to ensure that vendors working with legal marijuana businesses do not have their banking services taken away. Landlords, chemists, security companies, and more have had their bank accounts frozen for doing business with state-sanctioned marijuana businesses

Among those signing the letter were senators Elizabeth Warren (D-Mass.), Jeff Merkley (D-Ore.), Ron Wyden (D-Ore.), Kirsten Gillibrand (D-N.Y.), Patty Murray (D-Wash.), Bernie Sanders (I-Vt.), Al Franken (D-Minn.), Angus King (I-Maine), Lisa Murkowski (R-Alaska) and Cory Booker (D-N.J.).

“Most banks and credit unions have either closed accounts or simply refused to offer services to indirect and ancillary businesses that service the marijuana industry,” the letter says. “A large number of professionals have been unable to access the financial system because they are doing business with marijuana growers and dispensaries. This long list of professionals includes chemists who have had their checking accounts closed due to their role in testing marijuana for the presence of harmful materials like arsenic; the security industry, which marijuana businesses heavily rely on due to the massive amounts of cash they handle; and lawyers offering legal services to marijuana businesses, who have reported banks denying applications for bank accounts and credit cards.”

Legitimate, indirect businesses have been unable to open checking accounts and accept credit cards or checks, the senators say. In some cases they have also lost access to existing accounts, such as retirement accounts, and have been forced to pay their employees, taxes, and bills in cash. “Locking lawyers, landlords, plumbers, electricians, security companies, and the like out of the nation's banking and finance systems serves no one's interest,” they wrote. "Forcing all these direct and indirect businesses to operate in cash not only creates a huge target for criminals, but also complicates the collection of state and federal taxes. This business environment is an invitation to tax fraud, robberies, money laundering, and organized crime."

The letter urges FinCEN to issue updated guidance on the issue without delay.