ST. PAUL — A state commission set in motion Wednesday major reductions to prison sentences for many drug offenders, a move that would put Minnesota’s drug laws more in line with other states and reduce a prison population that’s stretching the state’s facilities.

The Minnesota Sentencing Guidelines Commission approved a measure that would cut prison sentence guidelines for first-degree drug possession nearly in half and could mean probation for second-degree offenders rather that the current four-year prison sentence. Members of the panel expressed concern that the state’s current laws are too harsh on methamphetamine, heroin and cocaine users, punishing lower-level drug offenders with sentences that should be reserved for major drug dealers.

“The prior guidelines were too severe,” said Mark Wernick, a commissioner and former Hennepin County Judge.

But the reductions aren’t final yet. The changes need to come up for a public hearing and final vote next month, and the Legislature has a window to veto them before they would take effect in August.

The move comes amid a nationwide re-examination of drug laws to ensure authorities aren’t sending lower-level and first-time drug offenders away for long prison sentences. And it comes as Minnesota prisons are running out of space. Supreme Court Justice Christopher Dietzen, the group’s chair and author of Wednesday’s proposal, said it could free up to 700 beds.

“I just think that there’s a realization … that something needs to be done to improve our drug sentencing policies,” Mark Haase, an attorney and lobbyist for the Minnesota Association of Criminal Defense Lawyers, said ahead of Wednesday’s meeting.

The state’s sentence guidelines are a critical starting point for judges. The commission generally recommends changes to the Legislature, but the judges and attorneys on the panel are preparing to cut the guidelines on their own to save the Legislature — which hasn’t made major changes since the ‘90s — from the political pain of appearing soft on crime.

Dietzen wrote that the result of the inaction is that Minnesota’s population of imprisoned drug offenders has jumped 171 percent in the last two decades, and judges are often issuing lower sentences than the guidelines suggest. Current state law suggests a seven-year sentence for first-degree drug possession charge — 25 grams of heroin, methamphetamine or cocaine.

The commission lowered the sentence to four years. The current four-year sentence for second-degree possession would likely become probation.

Wernick said the commission felt it needed to act after seeing the state’s response to the overturning of a law that called for higher sentences for crack cocaine than powder cocaine in the 1990s. Rather than cutting penalties for crack, lawmakers raised penalties for other drugs, he said.

The commission’s changes maintain harsher sentences for first-degree drug sales and reserves more punishment for dealers who sell drugs across state lines, operate in more than three counties or use a gun. It also maintains a stiff sentence for methamphetamine manufacturing.

Dietzen called it a “palatable balance between punishing kingpins and treating addicts.”

But Republican Rep. Tony Cornish said he thought the justice’s proposal still went too far, and suggested it was driven by a desire to ease crowding in Minnesota prisons.

“There seems to be a rush to solve this by lessening sentences,” said Cornish, a former police officer who sits on a task force studying Minnesota’s prison populations. “It would be a tough sell. I don’t think the county attorneys or law enforcement want to go that far.”