After four years of deliberation, the Maryland school board passed new disciplinary regulations Tuesday that will end a zero-tolerance policy that sent home large numbers of boys, special education students and African-Americans for minor infractions.

Education experts said they believe Maryland is among the first states to take the step toward a less-punitive disciplinary code that will require administrators to use suspensions as a last resort. Students who are violent or bring weapons to school will still receive swift and tough punishment.

While the new regulations have support among advocates and some administrators, they have drawn criticism across the state for taking disciplinary decisions out of the hands of local officials. State officials received more than a thousand letters from opponents of the plan, somewhat less than those in support.

In fact, said board member Donna Hill Staton, the new regulations will give school officials, particularly principals, more discretion when students are caught breaking the rules. The new policy, she said, "would not impose shackles but rather be liberating and empowering" to local officials. "Certainly, zero tolerance isn't freedom."

By next fall, school districts across the state must inform the state board how they have changed their policies to reduce the number of long-term suspensions as well as the disproportionate suspensions of students of color and special education students.

Advocates of the new disciplinary measures have said the old policies put suspended students at greater risk of getting into trouble later in life and ending up in prison.

Long-term suspensions will be allowed only for students who pose an "imminent threat of serious harm to other students or staff" or for students who are chronically disruptive.

The new rules require school officials to let students attend school during an appeal of a suspension or while officials are considering longer-term suspensions.

In 2009, when the state school board began questioning what members saw as the misuse of discipline, large numbers of students were being suspended for not attending school, talking back to a teacher or other minor infractions.

Students in Baltimore County who were found with even small amounts of alcohol could be put in an alternative school for a semester. An Anne Arundel County girl was suspended for carrying pepper spray in her pocketbook to protect herself as she walked to school in the early-morning darkness, as were two Easton lacrosse players who were found to have a pocket knife and lighters, used to fix their sticks, in their gym bags. And a Dorchester County ninth-grader was suspended for nearly a year without any educational services.

Jane Sundius, the Open Society Institute's education program director in Baltimore, who fought for the changes, called the board's nearly unanimous vote an act of courage.

"This is truly a civil rights issue, perhaps the civil rights issue in education," she said. "I think the state school board recognizes that."

liz.bowie@baltsun.com