Colleagues and students say Lanner would call parents to persuade them to let their children travel to Israel with him, board students at his Paramus home so they could attend yeshiva, and inspire them to become better Jews. To some, he was a substitute father.
But in recent months, more than 25 former students have come forward to say that Lanner, a leader in the Orthodox Union's National Conference of Synagogue Youth, sexually, physically, and verbally abused them for decades.
The students, now in their 30s and 40s, said Lanner kissed, fondled, and hit teenage girls and kneed some boys in the groin. His accusers also say he attacked a man with a knife.
Lanner, 50, has denied breaking the law and has never faced criminal charges.
But he resigned as director of regions for the New York-based youth group last month after The Jewish Week of New York published many of the allegations. Two New Jersey prosecutors have also begun criminal investigations and the Orthodox Union has begun a probe to determine whether it was responsible for covering up complaints about its former employee.
Rabbi Yosef Blau, a Yeshiva University counselor and one of Lanner's strongest critics, said the rabbi was largely protected by the Orthodox Union, a venerable institution with a membership of nearly 1,000 synagogues that also puts the seal of approval on kosher food.
"I think that they were so enamored with his success and accomplishments that they didn't want to hear problems," Blau said.
"There was a code of loyalty here at the same time, and also he was very scary," said Naomi Freistat, a 41-year-old doctor who said Lanner kissed and fondled her a dozen times and punched her in the stomach when she was 15. "This was a man where you didn't know what was coming next."
Lanner, who recently separated from his wife, said he has violated Orthodox Jewish law by having physical relationships with former students--none of them teenagers--but hasn't broken any criminal laws.
He denied the allegations of Freistat and others printed in The Jewish Week and said he couldn't recall others.
The author of The Jewish Week's article, editor and publisher Gary Rosenblatt, said he spoke to 15 to 18 people who complained about Lanner, and has received letters from a dozen more.
"Some of them didn't know there were any others," Rosenblatt said.
Prosecutors in Bergen and Monmouth counties are investigating allegations in the article. One woman said Lanner suggestively brushed up against her while she was a student at the Frisch School in Paramus.
Lanner has said the woman, Marcie Lenk, could have misinterpreted his actions. He said Lenk was living at his home at the time and never spoke to him about feeling uncomfortable.
"If you felt threatened, idiot, why did you come?" Lanner said. "Why did your parents let you come?"
Freistat, a podiatrist in New York, said she met Lanner when she traveled from Wilkes-Barre, Pa., to retreats in New Jersey. Freistat said Lanner persuaded her mother to let her go on his six-week trip to Israel in 1974.
Lanner asked Freistat to kiss him on the cheek the first week of the trip, and on the second week summoned her outside--"it was always outside," she said--and kissed and fondled her. She endured the contact a dozen times, she said, fearing she would be sent home.
She said she tried to pull away the last time he approached her in a Jerusalem courtyard near her hostel.
"He said 'Don't walk away from me,'" Freistat said. "He punched me in the stomach. All I remember is just looking up at him and saying 'You just punched the wrong girl.'"
Freistat said she and another girl on the youth group spoke to two rabbis about Lanner's conduct, but that he went unpunished. After the article was published, the Orthodox Union set up a commission to find out "who knew what and when did they know it," said Mandell I. Ganchrow, president of the Union.
Freistat called the Orthodox Union "a boys' club," while other students said the organization let Lanner's conduct go unchecked because he made a lot of money for it.
Said Freistat: "He was smart enough to pick on little kids."