The Cooperative Credit Union Association, which advocates for credit unions in Delaware, Massachusetts, Rhode Island and New Hampshire, has come out in support of a new bill co-sponsored by Sen. Elizabeth Warren that would remove the threat of a federal crackdown on marijuana.

The STATES Act, which is also sponsored by Sen. Cory Gardner (R-Colorado), would let states choose how to regulate marijuana without having to worry about the federal government intervening. The bill would also enable pot businesses to access federal banks and financial institutions, a potentially huge breakthrough for the industry.

“This proposal protects Massachusetts as well as any future or current cannabis-legal state from federal prosecution,” Paul Gentile, president and CEO of the CCUA, wrote in a letter to Warren. “It recognizes that if states move forward on emerging issues, such as medical marijuana, recreational marijuana and others, that such activity will be lawfully and legally carried out.”

The legislation has also received backing from the Maine Credit Union League and the Mountain West Credit Union Association. Gentile also said that passage of a bill such as the STATES Act would give credit unions the go ahead to start banking marijuana.

“Most importantly, the measure expressly lifts restrictions that prevents Massachusetts credit unions from providing quality banking services to the emerging legal marijuana industry, which is currently either without financial services and/or clearly underserved,” he wrote. “Your proposed legislation will help credit unions open the welcome door to both businesses and consumers as their volunteer boards of directors may determine to be appropriate to meet the financial services needs of those most in need.”

Aside from a few standouts, banks and credit unions have largely been unable to service the marijuana industry because it is still illegal at the federal level. The issue got even more complicated when U.S. Attorney General Jeff Sessions rescinded the Cole Memo, an Obama administration guidance that essentially said the federal government would not interfere with marijuana programs in states in which they are legal.

Passage of the STATES Act could open financial institutions in Massachusetts to an industry that is predicted to be valued at $1 billion by 2020.