WASHINGTON — The former head of USA Gymnastics pleaded the Fifth at a congressional hearing on Tuesday, refusing to answer questions about his role in the sex abuse scandal surrounding Olympic team doctor and serial predator Larry Nassar.

"Shame!" one former gymnast shouted as Steve Penny hurried out of the hearing room with his lawyer in tow.

Penny, who resigned his post under fire last year and has not spoken publicly since, was subpoenaed to appear before a Senate Commerce subcommittee investigating the failure to protect young athletes.

He repeatedly invoked his privilege against self-incrimination as he was asked about his handling of of the first allegations in the summer of 2015.

"I would like to answer your question but I have been instructed by my attorney to assert my rights under the Fifth Amendment," Penny said.

Sen. Richard Blumenthal, D-Conn., told Penny that he had the right not to respond, but added, "Documents will speak for you." He then asked about a document suggesting that Penny had concerns about Nassar as far back as 2013 and a 2014 email that referred to a "code of silence."

Steve Penny, you would only plead the fifth if you have stuff to hide and clearly, you do. You are an absolute coward. — Kaylee Lorincz (@KayleeLorincz) June 5, 2018

Penny declined to answer again and was excused.

Amy Moran Compton, a former gymnast who said Penny was slow to investigate a different coach who abused her, broke decorum by standing and shouting "Shame!" As Penny left the building in silence, former national team member and Nassar survivor Jeanette Antolin called him "a coward."

"It's ludicrous that he got to leave, that he didn't have to stay and listen," Antolin told NBC News. "The hearing was disappointing to me. I don't think there were many answers."

The session did reveal new details about how USA Gymnastics handled the initial allegations against Nassar:

Penny ordered six of the organization's top officials not to discuss the matter with anyone.

USA Gymnastics informed Nassar of athlete concerns about his so-called therapies even before it reported him to the FBI.

USA Gymnastics fired Rhonda Faehn, the director of the women's program and the first official to receive a complaint about Nassar, after she disclosed that she had been summoned to appear before the Senate subcommittee.

Penny has been accused of covering up allegations against Nassar. He waited more than five weeks to notify the FBI of allegations and never informed Nassar's other employer, Michigan State University, where he continued to treat and molest patients for more than a year.

Penny has denied to NBC News, through his attorney, that there was any cover-up. He is "repulsed" by Nassar's crimes, his attorney said in a statement.

USA Gymnastics maintains that it didn't share information about Nassar with other gymnasts, their parents or Michigan State because the FBI had advised the organization not to interfere with its investigation, but an email turned over to the subcommittee raises questions about that explanation.

"You are instructed not to have any conversations with anyone concerning this issue until further notice," Penny wrote in the July 21, 2015, email to board members Jay Binder, Paul Parilla and Peter Vidmar and top executives Faehn, Ron Galimore and Renee Jamison.

The email said that the following day, USA Gymnastics' lawyers planned to tell Nassar that athletes were "uncomfortable" with his techniques and that he would not be attending an upcoming event. Yet it wasn't until July 27 that Penny contacted the FBI about Nassar.

In fact, the Nassar probe was such a closely held secret that eight months after the first complaint, a USA Gymnastics staffer who was not in the loop invited the doctor to speak at a conference — and learned for the first time that he had been dismissed as team doctor, another email shows.

Those emails were turned over by Faehn, who also provided a July 13, 2015, email in which Penny told her to arrange for a USA Gymnastics consultant hired to determine if abuse had occurred to have one-on-one interviews with Olympic gold medalists Aly Raisman and McKayla Maroney.

"I was upset and confused by the email," Faehn told the subcommittee. "I did not want to ask the athletes to be interviewed while excluding their parents and coaches. I therefore refused to contact the athletes as instructed by Penny."

USA Gymnastics President Kerry Perry, left, and and Rhonda Faehn during a gymnastics competition in March. Amy Sanderson / Cal Sport Media via AP Images

Faehn was the first person at USA Gymnastics to receive a complaint about Nassar, after the coach of national team member Maggie Nichols overheard a disturbing conversation between Nichols and Raisman.

Nichols told the coach, Sarah Jantzi, that Nassar massaged her groin for a knee injury three times and sent her a private message saying she looked beautiful in her prom dress.

"I immediately called Penny and told him in detail about the concerns Jantzi shared with me," Faehn said in her prepared testimony. "Penny told me he would call Jantzi and the parents of the gymnasts right away."

Some of Nassar's victims have criticized Faehn for not going immediately to police. But she said Penny told her not to take any action.

"He told me not to say anything or do anything because he was going to handle everything going forward," she wrote. "And he told me he was going to report the concerns to the proper authorities, which I assumed included law enforcement."

Despite her central role, Faehn said she was never interviewed by any authorities until three weeks ago, when the Texas Rangers police agency, which is looking into Nassar's abuse of athletes at a ranch used as the national gymnastics training center, contacted her.

Faehn was a senior vice president until last month, when she was asked to resign during a phone call with current USA Gymnastics president Kerry Perry — after she informed Perry that the subcommittee wanted her to testify and could subpoena her if she refused.

She was asked by the subcommittee if she believed that she was terminated because she was about divulge information that would put USA Gymnastics in a "bad light."

"I really don't know," she said. USA Gymnastics did not immediately respond to a request for comment.

The third witness to appear at the hearing was former Michigan State University president Lou Anna Simon, who resigned this winter amid outrage that the school failed to act on multiple complaints about Nassar's so-called treatments.

Simon apologized but was unable to identify a single specific thing she or other officials had done wrong — even though MSU recently agreed to pay a record-setting $500 million settlement to more than 300 former Nassar patients.

"Not a day goes by without me wondering what we missed and what could have been done to detect his evil before a former youth gymnast filed her complaint with the MSU police in 2016," said Simon, defending the university investigator who cleared Nassar after a 2014 complaint.

The subcommittee also accepted written statements from former USA Gymnastics national team coordinator Martha Karolyi and former U.S. Olympic Committee president Scott Blackmun, who said they could not attend for medical reasons.