While Congress expects to renew protections for medical cannabis laws next month, pro-cannabis advocates worry Attorney General Jeff Sessions will crackdown on the law last minute.

For three years, Congress has been maintaining the Rohrabacher-Blumenauer policy, which prohibits the Justice Department from using federal funds to prevent states allowing medical cannabis from carrying out their laws. The amendment will soon expire unless Congress renews it.

Advocates are worried about last minute intervention from AG Sessions who called cannabis “only slightly less awful than heroin.” He had asked congressional leaders to remove the policy, since it restricted the Justice Department from enforcing the federal Controlled Substances Act. The act categorizes cannabis as a Schedule I drug, which claims it has a high potential for abuse and no known medical uses. 

Sessions faces a Congress filled with cannabis community allies from states where medical cannabis is legal. Each time the house had approved new Rohrabacher-Blumenauer language for the measure, protections for these states increased.

Sessions could direct U.S. attorneys to go after social-use states by prosecuting anyone in the industry, since social cannabis does not have the same protections as medical cannabis. Two years ago, Congress rejected a bipartisan amendment which would prohibit federal authorities from prosecuting cannabis cases in states where it is legal.

Earlier in August, AG Sessions’ task force on crime reduction and safety recommended no new changes to the Department of Justice’s approach to cannabis, recanting an Obama Administration directive to leave it with the states.