Many of today’s principals would be likely to throw the book at a student who pinned down a classmate and clipped his hair, as Republican presidential candidate Mitt Romney did as a high school senior in 1965.

Romney was not disciplined at the time. If such an attack happened in the public schools of 2012, it would probably lead to suspension and might also be referred for expulsion, a number of local school leaders said following a Washington Post report of the incident involving Romney.

A call to police would probably also be in order because it would be considered an assault, said Alan Goodwin, principal of Walt Whitman High School in Bethesda.

“It would be taken very seriously,” Goodwin said. “Even using the scissors would be considered using a weapon. It would not be an acceptable prank.”

Based on recollections of five fellow students, The Washington Post reported this week that Romney returned from spring break at his private all-boys school in Michigan to notice that a classmate — the object of teasing in the past and presumed by others to be gay — now had bleached-blond hair that draped over one eye.

The fellow students told The Post that Romney led his friends in tackling the teenager, pinning him down and snipping his hair with a pair of scissors. The teen cried and screamed for help, according to the classmates, and was out of school for a time, later returning with his shorter hair back to its natural brown color.

Romney said Thursday he did not recall the attack. In an interview with Fox News, he said: “I participated in a lot of hijinks and pranks during high school, and some might have gone too far, and for that I apologize.” He also said he had “no idea what that individual’s sexual orientation might be,” which was not “something we all discussed or considered” in the 1960s.

The incident comes to light amid increasing concern about school bullying and as efforts are underway nationally to reduce adolescent torment, which has been connected with teen suicide and other problems.

“The cutting off of hair — that crosses a line, no matter how you look at it,” said Gene Streagle, a former Howard County principal who is now executive director of the Maryland Association of Secondary School Principals. “If that happened in my school, they would be gone for a couple of days, minimum.”

Decisions about the severity of discipline include consideration of whether an incident is a repeat offense or a one-time mistake, Streagle said. He noted that the victim’s shorn hair would make the personal humiliation more lasting, and said it would be important to send a clear message to the school and larger community that, “You just don’t do this.”

In today’s world, such discipline could also have lasting effects.

College applications now routinely ask about disciplinary violations, meaning that a student might have to explain transgressions at some length.

“It would be just like with the lacrosse players,” Streagle said, referring to a high-profile Easton, Md., case that left two athletes headed to a game suspended for having a knife and lighter to repair their lacrosse sticks. The teens worried through the college application process, not applying to certain schools because they feared that the nature of their offenses — deemed possessing a weapon and an explosive device — would be misconstrued.

Private school discipline is an even more closed world than public school discipline, and several private schools contacted did not return calls or agree to be interviewed.

In a statement, St. Albans School in the District said it does not tolerate demeaning behavior and reacts swiftly to bullying incidents. “Depending on the case, the initial response might be a conversation between the bully and a counselor or chaplain,” the statement said. “If the situation does not improve, the family may be contacted, and the case may be brought before one of the discipline committees....which will recommend any disciplinary action.”

Michael A. Durso, a Montgomery County school board member who as a principal in Maryland, Virginia and the District, said he remembers the era of the 1960s and that “there were a lot of things that people looked the other way on.”

Nearly 50 years later, he said, “I don’t see how I could not suspend those involved.” When no action is taken, he said, “the message is that it’s okay.” If multiple students were involved, he added, school leaders would investigate to determine whether all would be punished equally or some disciplined more severely.

“I think a lot of it is what is the tone of the school, what has been accepted in the past,” he said.

Some who work with bullying prevention efforts said tough responses are needed for such incidents.

“If that happened in a school today, I would hope the police would be called,” said Nancy Willard, of Embracing Digital Youth, who works with anti-bullying efforts nationally.

Willard said she had a hard time fathoming that, according to the story, the attack did not result in discipline but that the victim was later thrown out of the prep school for smoking a cigarette.