On Jan. 4, U.S. Attorney General Jeff Sessions allowed federal lawyers to resume marijuana prosecutions in places where pot is legal under state law.
How that affects Ohio's nascent medical-marijuana program, however, remains murky.
Sessions rescinded a 2013 memo in which President Barack Obama's administration declared it would not block states from legalizing marijuana as long as officials act to keep it from migrating to places where it remains outlawed and to keep it out of the hands of criminal gangs and children.
The move by President Donald Trump's attorney general might cause confusion about whether it's OK to grow, buy or use marijuana in states that have legalized the drug because long-standing federal law prohibits doing so.
Last week, pot shops opened in California, launching what is expected to become the world's largest market for legal recreational marijuana. And a Gallup Poll released Jan. 4 showed 64 percent of Americans believe the drug should be legal.
Sessions has been a foe of marijuana legalization, but in a 2016 TV interview, Trump said he would not seek to shut down pot operations in states that had legalized it.
"I think it should be up to the states," Trump said.
When asked Jan. 4 for the president's position on marijuana, White House Press Secretary Sarah Sanders said: "The president strongly believes we should enforce federal law."
She said the new guidance empowers federal prosecutors to go after large-scale pot producers and distributors.
The new Justice Department guidance allows prosecutors to target California and the seven other states that have legalized recreational marijuana.
Exceptions to the rule
Such states as Ohio that have legalized medical marijuana have an extra protection.
A small section of the federal budget, known as the Rohrabacher-Blumenauer or Rohrabacher-Farr amendment, prohibits the Justice Department from spending money to enforce federal law against medical marijuana in states where it's legal. That amendment, which Obama signed into law in December 2014, remains in place at least until Jan. 19, when a stopgap budget resolution is set to expire.
Many people expect the medical-marijuana amendment to be renewed -- as it has been since 2014 -- because it has bipartisan support on Capitol Hill.
Thomas Rosenberger, executive director of the National Cannabis Industry Association of Ohio, said the presence of Sessions at the helm of the Justice Department has raised new concerns about the amendment's future.
"At this point, it's hard to say," he said. "I'm still optimistic about it continuing to be renewed. But there's no question that it's more in doubt than it's been in years past."
Ohio is in the process of licensing growers, processors and dispensers of medical marijuana, which under the state's 2016 statute is to be available to patients by September.
The Ohio Department of Commerce, which is responsible for overseeing most of the process, is following state law in moving to offer medical marijuana, spokeswoman Stephanie Gostomski said Jan. 4.
"Our responsibility is to fulfill all statutory mandates in establishing Ohio's medical-marijuana program. The department cannot speculate on any decisions made at the federal level, but our program officials will continue to monitor any developments," she said in a statement.
Ohio Attorney General Mike DeWine declined to comment on the new guidance from the Justice Department.
U.S. Sen. Sherrod Brown, a Democrat, said Sessions should focus his energies elsewhere.
"The Justice Department should focus on supporting Ohio law-enforcement efforts to combat the opioid and heroin epidemic, not wasting valuable time and resources going after families using medical marijuana to treat cancer or Parkinson's," Brown said in an email.
Sen. Rob Portman, a Republican, didn't respond to a request for comment.
In a statement, U.S. Attorney for the Southern District of Ohio Benjamin C. Glassman said marijuana long has been illegal under federal law. But he said the Obama-era memo and Sessions' guidance rescinding it both acknowledge that federal prosecutors have to prioritize how to use their limited resources.
"I have said before that the opioid epidemic is the public health and safety crisis of our lifetime, and I have also pointed to the disturbing increase in stimulant drugs like cocaine and methamphetamine," Glassman said.
At the local level, several central Ohio cities have been deciding whether to allow medical-marijuana businesses within their boundaries.
For example, Grove City and New Albany have banned such businesses, but Hilliard and Johnstown have opened their doors to them.
New Albany City Council initiated its ban of marijuana-cultivation, processing and retail-dispensing businesses Nov. 28, with city attorney Mitch Banchefsky citing medical marijuana's illegal standing under federal law as the reason. Although medical marijuana is legal in Ohio and the federal government wasn't enforcing laws banning it, nothing would prevent the government from doing so in the future, he said at the time.
Banchefsky said Jan. 4 that New Albany's ban was more about taking the federal law under consideration than any anticipation of a possible federal adjustment. He said policy might change but federal law has been consistent in its prohibition.
Some groups are applauding Sessions' move.
Anti-legalization group Smart Approaches to Marijuana said modern turbocharged pot can be addictive -- especially for adolescents -- and that drugged-driving accidents have spiked in such states as Colorado, where recreational marijuana has been legalized.
The group's president, Kevin Sabet, said on a conference call with reporters that federal authorities have never focused enforcement on low-level users and that the new Justice Department guidance will prompt U.S. attorneys to go after the big players in the industry.
Carrie Eickleberry of the Ohio chapter of the National Organization for the Reform of Marijuana Laws said that because the state's medical-marijuana law was the product of the General Assembly rather than a voter initiative, she expects it to be strongly defended.
"I think the legislature is going speak up loudly," she said.
The Columbus Dispatch reporter Randy Ludlow, ThisWeek reporter Sarah Sole and The Associated Press contributed to this story.