Despite marijuana being a federally illegal drug, U.S. Sen. Brian Schatz announced legislation Thursday that would allow doctors at the U.S. Department of Veterans Affairs to recommend pot to veterans in 31 states with medical cannabis programs.

The congressional bill includes five-year safe-harbor protection for veterans using the drug and would direct the VA to research how cannabis could “help veterans better manage chronic pain and reduce opioid abuse.” Safe-harbor protection means a veteran would not be subject to punishment by the federal government for marijuana possession.

“In the 31 states where medical marijuana is legal, patients and doctors are able to see if marijuana helps with pain management. Our veterans deserve to have that same chance,” Schatz said in a news release. “This bill does right by our veterans, and it can also shed light on how medical marijuana can help with the nation’s opioid epidemic.”

As a federal entity, the VA is prohibited from certifying medical marijuana patients or recommending it as a treatment option, a spokeswoman said.

The Drug Policy Forum of Hawaii said the legislation would protect veterans from more powerful and addictive drugs.

”This is especially important for Hawaii with its many veterans who will no longer be confined to two bad options: refraining from using a medicine that can help them or keeping that use a secret,” said Carl Bergquist, executive director of the Drug Policy Forum.

In 2015 Hawaii added post-traumatic stress disorder to the list of eligible conditions for the use of medical pot.

“This bill would help allay any fears of adverse VA consequences for these veterans as their bodies heal,” Bergquist added.

The state legalized the medical use of cannabis in 2000, but patients had no legal way to obtain the drug until dispensaries began operating in August 2017. There were 22,078 medical marijuana patients statewide as of Aug. 31.