US attorney general Jeff Sessions has issued a memo to federal prosecutors around the country, directing them to seek harsher penalties for low-level offenses—bringing back the type of policy that contributed to the ballooning mass- incarceration system in the United States.

“It is a core principle that prosecutors should charge and pursue the most serious, readily provable offense,” the memo says. “By definition, the most serious offenses are those that carry the most substantial guidelines sentence, including mandatory minimum sentences.”

This statement, released Friday (May 12), rolls back a crucial Obama-era policy in the Justice Department, aimed at mitigating harsh sentencing laws imposed in the past. In 2013, Obama’s attorney general Eric Holder instructed federal prosecutors not to charge nonviolent drug offenders with crimes that carry mandatory minimum sentences he called “draconian.”

Sessions’ opposite, “tough on crime” attitude, which he has espoused since the beginning of his tenure, is being widely compared to the 1970s “War on Drugs” that wreaked havoc on minority communities in previous decades. That effort really ramped up in the late 1980s with the introduction of mandatory minimums for drug crimes, and peaked with the Clinton-era 1994 crime bill that established further harsh sentences and funneled billions into the nation’s prisons.

Reactions from criminal-justice reform circles have been unanimous, from lawmakers and law enforcement leaders to advocacy groups and criminologists. Holder himself responded, calling the policy “dumb on crime,” “ideologically motivated,” and “cookie cutter.” Here’s a selection of other statements:

Rep. Cedric Richmond, chairman of the Congressional Black Caucus: “Our biggest concerns about Attorney General Sessions are becoming reality,” he said in a statement. “It is widely known that every $1 we spend on mass incarceration makes the country less safe, but Attorney General Sessions has not learned this lesson and is determined to continue the war on drugs with extremely brutal force.” On the Obama-era policy Session has rolled back: “This was fiscally smart and compassionate policy that started to stem the tide of mass incarceration in our country. “

Brett Tolman, former US attorney for Utah and a representative of the Law Enforcement Leaders group: “The Justice Department’s expected shift to prosecuting and incarcerating more offenders, including low-level and drug offenders, is an ineffective way to protect public safety. Decades of experience show we cannot arrest and incarcerate our way out of America’s drug problem”

Udi Ofer, director of the American Civil Liberties Union’s Campaign for Smart Justice: “Jeff Sessions is pushing federal prosecutors to reverse progress and repeat a failed experiment—the War on Drugs—that has devastated the lives and rights of millions of Americans, ripping apart families and communities and setting millions, particularly Black people and other people of color, on a vicious cycle of incarceration.”

It’s important to note that the federal part of the US criminal-justice system is a small chunk of the whole (about 13% of US inmates are in federal prisons) and that the tide of reform isn’t likely to turn back on the state and local level. However, the federal prison population is expected to grow under Sessions’ watch, considering both his battle against drug offenses and the Trump administration’s immigration crackdown.