"I think that the statement of the Attorney General is that it is still illegal at the federal level and I support that", he said. Despite Donald Trump's campaign promise to respect states' rights to implement their own marijuana laws, Sessions announcement that he's repealing Barack Obama's Cole Memo breaks that promise.
The new USA attorney in Massachusetts, Andrew Lelling, a Trump appointee who was confirmed by the Senate in mid-December, called marijuana "a unsafe drug" in his statement on Sessions' action.
President Trump is under fire from veterans' groups who are accusing his administration of putting personal politics ahead of their health.
Gov. Kate Brown said rolling back federal marijuana policy will disrupt the state's economy. California led the way in 1996, when voters approved marijuana for medical use.
The marijuana business has since become a sophisticated, multimillion-dollar industry that helps fund some government programs.
Forty-six states - including Sessions' home state of Alabama - have legalized some form of medical marijuana in recent years, according to the National Conference of State Legislatures.
Under the Sessions policy reversal, a cancer patient now using a marijuana-based drug to ease pain or nausea may have that right taken away.
States that have legalized medical marijuana have fewer deaths related to opioid abuse. The Trump Administration must put patients' rights first, and I will not stand for backwards attacks on the progress made in Pennsylvania to provide medicine to those in need.
Responses from senators on Capitol Hill came swiftly.
Among the most vocal was Senator Cory Gardner. "You're only going to ask that question if someone has a hit for cannabis on a post-offer, pre- employment, and you're going to make it clear that you don't want to know what that condition is".
However, Todd of Drug Policy Alliance said removing this policy "creates a lot of uncertainty" and represents a "direct threat to access".
If marijuana is grown from scratch in a state where it's legal and targeted for sale and use only in that state - I'm not seeing how the Feds can claim jurisdiction. The American people overwhelmingly support the legalization of marijuana and oppose federal intervention in state marijuana laws by even wider margin. The protections apply to 46 states, including Pennsylvania.
Organizations such as Smart Approaches to Marijuana have praised the decision, saying it will cut off large investments to the industry and keep it from becoming like "Big Tobacco". It's called House Resolution 1227: the Ending Federal Marijuana Prohibition Act.
In rescinding the three memos Thursday, Sessions advised prosecutors to "follow the well-established principles that govern all federal prosecutions".
To that end, Billy Williams, the USA attorney for OR, was saying all the right things on Thursday about how his office planned to proceed: "We will continue working with our federal, state, local and tribal law enforcement partners to pursue shared public safety objectives, with an emphasis on stemming the overproduction of marijuana and the diversion of marijuana out of state", he said in a statement.
"By continuing to pour billions of dollars down the drain with our archaic marijuana policies, we stifle our economy, society, and criminal justice system and leave the people of Hawai'i and millions more devastated - all for a substance that is far less unsafe and harmful than alcohol. And I am astonished to hear people suggest that we can solve our heroin crisis by legalizing marijuana - so people can trade one life-wrecking dependency for another that's only slightly less terrible", Sessions told law enforcement officials in a speech a year ago.