DENVER – Whether to crack down on marijuana in states where it is legal is a decision that will now rest with those states’ top federal prosecutors, many of whom are deeply rooted in their communities and may be reluctant to pursue cannabis businesses or their customers.

When he rescinded the Justice Department’s previous guidance on marijuana, Attorney General Jeff Sessions left the issue to a mix of prosecutors who were appointed by President Trump’s administration and others who are holdovers from the Barack Obama years.

Legal experts do not expect a flood of new cases, and people familiar with the job of U.S. attorney say prosecutors could decide against using already limited resources to seek criminal charges against cannabis companies that abide by state regulations or their customers.

“There are higher priorities: terrorism and opiates to start with,” said Rory Little, a former prosecutor and a professor at the University of California Hastings College of Law. “You also have to draw the jury pool from the local people, who appear to generally support the state policy. You’re not going to waste your resources on cases you can’t win or cases your community is against.”

Until Sessions’ announcement on Thursday, federal prosecutors followed guidelines laid out in the so-called Cole memo, which was issued by the Justice Department during the Obama administration. The memo discouraged prosecutors from going after people participating in the marijuana trade in states where recreational marijuana is legal, except in cases with aggravating factors.

Sessions revoked that document and others, citing the fact that pot remains illegal under federal law.

Federal prosecutors are not elected, but they often have long histories working in their districts. They are surrounded by attorneys who have spent their careers arguing federal cases before judges who can make their displeasure with a U.S. attorney known in sentencing decisions and in the scheduling of cases. That environment will not change because of a memo from the attorney general, Little said.

But the change will undoubtedly create some confusion and an uneven landscape, said John Walsh, the former U.S. attorney for Colorado appointed by Obama who left the office in 2016.

Prosecutors in Western states wanted guidance from the Justice Department when the likelihood of state marijuana legalization became clear in 2010 and 2011. They hoped to avoid a patchwork of prosecution strategies, Walsh said.

“When the policy is so broad and uncertain that it’s left case by case to different decision makers, it creates confusion and uncertainty that can be unjust,” Walsh said.

The author of the Obama administration’s policy, James Cole, told the AP it was intended to put states on notice that they had to regulate the industry and the federal government would still prosecute cases that threatened public safety. The goal, he said, was to encourage a tightly regulated industry letting legitimate businesses operate but keeping cartels and gangs out.

“I couldn’t immunize people through the policy, but it did give them a level of comfort that was enough for them to say, if I behave, we’re basically going to be OK,” Cole said.

The change, he said, removes “clarity and consistency” for an industry that depended on it.

U.S. attorneys around the country responded cautiously to Sessions’ announcement. Some issued written statements suggesting the change would not dramatically alter their approach to marijuana.

In Maine, U.S. Attorney Halsey B. Frank, who is a Trump appointee, and sworn in last October, has written about his personal opposition to recreational cannabis use.

On Thursday, Frank told the Portland Press Herald that he wanted to consult with his management team and evaluate how the new Justice Department memo might affect charging decisions in Maine.

In Colorado, U.S. Attorney Bob Troyer said his office will continue to focus on “identifying and prosecuting those who create the greatest safety threats to our communities around the state.”

Troyer took over the office on an acting basis when Walsh, the Obama appointee, left. In November, Sessions named him the interim U.S. attorney. Trump could nominate a replacement at any time or decide to keep Troyer, a career prosecutor and attorney.

The new U.S. attorney in Massachusetts, Andrew Lelling, a Trump appointee who was confirmed by the Senate in mid-December, called marijuana “a dangerous drug” in his statement on Sessions’ action. But he also said his office will focus on “bulk cultivation and trafficking cases, and those who use the federal banking system illegally” while considering its available resources, the seriousness of each crime and its effects.

In California’s Eastern District, newly sworn-in U.S. Attorney McGregor “Greg” Scott grew up in Humboldt County, deep in California’s famed “Emerald Triangle” marijuana-growing region. He later became a career state and federal prosecutor who has spoken favorably of a previous federal marijuana crackdown.

Scott’s spokeswoman, Lauren Horwood, said he declined to comment on the most recent federal move.

“The cultivation, distribution and possession of marijuana has long been and remains a violation of federal law for all purposes,” she later said in a statement. “We will evaluate violations of those laws in accordance with our district’s federal law enforcement priorities and resources.”

Brian Vicente, a Denver attorney who co-wrote Colorado’s 2012 constitutional amendment legalizing recreation marijuana, said the industry will closely examine the background of any new U.S. attorney nominees.

“If this is in any way accompanied by a changing of the guard through the appointment of very conservative, anti-marijuana candidates, that’s a red flag,” he said.

Walsh, the former U.S. attorney for Colorado, said sitting and incoming top federal prosecutors in pot-friendly states should rely on their staffs, who have years of experience investigating cases, to put marijuana in context with other priorities.

“Those people make decisions about which cases they can win and which cases are crucial,” he said.