Head of school Barbara Wagner will step down from her post at Marlborough School at the end of the academic year.

The announcement follows an investigation into the past alleged misconduct of an English teacher, centering on sexual harassment toward students. The all-girls school for grades 7-12, located at 250 S. Rossmore Ave., issued a public statement

“This summer, events came to light that were very serious and concerning,” the statement read. “The Marlborough Board of Trustees expeditiously moved to ascertain what and how events happened, and diligently worked to minimize the risk that similar incidents would happen again.”

Those events came to light at the end of June when former Marlborough student Mikaela Gilbert-Lurie published an essay online at www.xojane.com entitled “It Happened To Me: My High School English Teacher Told Me He Loved Me (And Nobody Did Anything).”

In the essay, Gilbert-Lurie does not explicitly name Marlborough or her teacher, Joseph Koetters, but word quickly spread through the school community.

Koetters was hired at Marlborough in 1999, and ascended to the head of the English department in 2001. He remained at the school until June 2013, when he took a different job at Polytechnic School.

Gilbert-Lurie wrote about her experiences as a 16-year-old, when Koetters was her teacher.

“When I emailed him asking if he would mind being interviewed for a newspaper article he responded with, ‘It’s a date,’” she said in the essay.

During the newspaper interview, Gilbert-Lurie details a very uncomfortable moment between the two.

“His hands brushed against my knee, rubbing the black nylon of my tights,” she said. “He blushed as I jerked away. It was a line I thought he wouldn’t cross, a physical barrier that I had trusted him to respect. I thanked him for the interview, and my friends asked me why I was so pale for the rest of the day. I said it was a migraine.”

The former student’s essay continues to detail interactions with her former teacher. She said she didn’t mention it to anybody for approximately three months, but eventually told her brother, they told her parents and then the family reached out to the school in 2012.

“He was not fired,” she said in the essay. “His only punishment was counseling. He’s still everyone’s favorite English teacher, and until the day I graduated he stared at me. Then he left to teach at another school. This is the first time I’ve told this story publicly, and I’m sorry there’s not a more satisfying ending. Some things just leave you feeling empty.”

As the story gained traction, the Marlborough Board of Trustees also became informed of the matter, officials said. They formed a special investigative committee last summer to look into the claims of misconduct against Koetters.

Last Friday, the board released a letter to the school community (which has since been published by multiple community members online), signed by board president Christine Ewell and the chair of the investigating committee (and also board member) Debra Wong Yang.

“Based on what we have learned, we have already implemented new policies and procedures to prevent similar misconduct and to ensure proper responses to any future allegations,” the letter starts. “The [investigation] revealed a pattern of misconduct by Koetters, including instances of improper physical contact and communications with multiple Marlborough students. The investigation also identified mistakes in judgment by Barbara Wagner, our head of school, in responding to allegations of misconduct. Finally, it revealed the need to improve school policies, procedures and training as well as to increase board oversight.”

In addition to Yang, who is a retired California state judge and former U.S. attorney, the investigative team was led by Mark Holscher, who is a former assistant U.S. attorney. He spent hundreds of hours investigating the matter — interviewing dozens of people and sifting through old emails, the letter said.

During the investigation, new complaints arose, alleging sexual harassment and inappropriate behavior by other adults at the school. There were two other instances, one in 2002 and another in 2005, which were related to different faculty members who were terminated at those times, the letter said.

The investigators also looked into a new allegation that came up during the investigation against Koetters alleging misconduct approximately a decade ago and 2005 allegations against Koetters by a different student, which were reported, like Gilbert-Lurie’s, to Wagner.

The letter said the investigators found Wagner “incorrectly questioned the veracity and motive of the student’s allegations” and said that she should have gone back to that complaint when she learned about Gilbert-Lurie’s, noting “the decision not to fully investigate the student’s complaint represented a serious error in judgment by the head of school.”

“The [investigation] found that, over the years he was at Marlborough, Koetters on many occasions attempted to engage students in improper conduct, often using his position of authority to prompt improper discussions and invitations for further contact,” the letter said.

In 2012, Wagner consulted with the then-board president and the school’s counsel, investigators said. She did not fire Koetters, but required him to attend anti-harassment training and ordered him to avoid all contact with Gilbert-Lurie, which he violated multiple times, the letter said.

“It is clear from the [investigation] that the head of school did not fulfill several crucial management and oversight responsibilities,” the letter said.

Board members said that a committee has been formed to reassess school policies and procedures, and that policies regarding sexual harassment and bullying were updated. Staff members have been provided new training by a psychologist, sexual harassment experts and an expert on student safety and teenage relationships. The school also has scheduled discussion groups for all grades.

At the end of the Friday correspondence to the school community, Wagner’s fate is addressed.

“The board is indebted to Barbara Wagner for her significant contributions and 26 years of dedication to Marlborough School,” it read. “Nevertheless, Ms. Wagner has requested to resign effective June 30, 2015, and the board has agreed to accept her resignation.”

The board has hired Wickenden Associates to conduct a search for a new head of school.

“The board’s most important priority is the safety of our students,” the statement released to the public concludes. “We have and will continue to diligently work to make every effort to protect them from any form of abuse or inappropriate conduct at Marlborough.”

Koetters has not been charged with anything, but according to the school, the Los Angeles Police Department and the Los Angeles Count District Attorney’s Office are in the process of conducting their own investigation, and the school is fully cooperating.