The police in Baton Rouge, La., are investigating whether a hazing episode at a fraternity may have played a role in the recent death of a 20-year-old Southern University student, university officials said Wednesday.

The student, Caleb Wilson, of New Orleans, died at 12:27 a.m. on Feb. 27, the East Baton Rouge Coroner’s Office said. A university investigation into his death started after rumors of “unsanctioned off-campus activities” began to swell, the university, whose full name is Southern University and Agricultural & Mechanical College, announced on social media. The activities are believed to have been organized by the Beta Sigma chapter of the Omega Psi Phi fraternity, the university said.

“We have been informed that the local authorities have launched an investigation into this tragic incident,” the fraternity said in a statement on its website on Feb. 28. “We have extended ourselves to them and are ready to assist in any way possible during this difficult time.”

The coroner’s office said that “the cause and manner” of Mr. Wilson’s death were still under investigation. The Baton Rouge Police Department, which is investigating Mr. Wilson’s death, did not immediately respond on Wednesday to an email or phone call seeking additional information.

“An off-campus incident is believed to have contributed to Caleb’s death,” John K. Pierre, the chancellor for the school, said on Feb. 27 in a Facebook message. “Southern University is cooperating fully with the Baton Rouge Police Department.”

It is unclear whether Mr. Wilson was a fraternity member.

Mr. Wilson was a junior at Southern University, a historically Black institution, majoring in mechanical engineering. He was also a member of the “Human Jukebox” Marching Band, the school’s prestigious collegiate musical group that incorporates dance and music and has performed at Super Bowls and presidential inaugurations.

“This tragic loss leaves a void in our Jaguar family,” the school said, referring to the university’s mascot. “Our thoughts and prayers are with Caleb’s family, friends, classmates, and loved ones during this incredibly difficult time.”

Southern University also said that it had begun a “student judiciary process” in the aftermath of Mr. Wilson’s death.

“Caleb was a bright and talented young man with a promising future ahead of him,” his family said in a statement provided to WAFB, a local television station. “We are committed to seeking the truth about the circumstances surrounding Caleb’s passing and ensuring that no other family has to endure such a tragedy.”

A candlelight vigil honoring his life was held on campus on Friday evening.

In recent years, there has been a crackdown on fraternity hazing at schools across the country, and several states have passed legislation to address the problem.

Earlier this year, four fraternity members at San Diego State University were charged with felony counts after a pledge was set on fire during a skit at a party last year.

In October, two men who were charged in the 2017 hazing death of a Pennsylvania State University sophomore were sentenced to two to four months in prison.

A courtroom can become a sort of time machine.

The criminal trial of Paul Geer, a former music teacher, played out in federal court in Albany, N.Y., last week. But testimony and photographic evidence transported everyone back to the 1990s and early 2000s to a town 125 miles away, Hancock, and to the Family Foundation School’s secluded campus in the woods.

The reform school is long closed and has settled several lawsuits by former students accusing Mr. Geer of sexual abuse over decades. But the trial brought the place back into the public spotlight.

There is a photo of a large basement lined with bunks. The female students slept there, beneath Mr. Geer’s home. There is the barn, where he held practice for his young singers.

Middle-age men and women sat in the witness stand and were asked the same question: “Do you see Paul Geer here today?”

They scanned the room, resting their eyes on the stout, bald, bespectacled man hunched at the defense table. Some knew him when he was in his 20s or 30s. Now he is 57.

They all pointed — him.

They were asked about how he terrorized them, or worse, decades ago, when they were teenagers.

In 2024, Mr. Geer was charged with six counts related to bringing three children across state lines to engage in sexual activity. The case led to a trial that began on Feb. 19.

On Friday, closing arguments took place. About a dozen former students who had mostly never met before, having attended the school at different periods, watched in the gallery. The jury began deliberating soon after.

Over the past week, witnesses were shown photographs of the place many have tried to forget. Their names have been redacted from public records in the case, but several have come forward in interviews and lawsuits.

“This is the isolation room where I had to stay for five days,” one former student, Elizabeth Boysick, 41, testified, looking at a picture of a tiny, windowless room. “It’s very hard to look at. Nobody should be treated like this. Especially children.”

The school was founded in the 1980s by Tony and Betty Argiros, a couple who had each struggled with addiction and built the place on the tenets of Alcoholics Anonymous and its 12-step program. Parents from surrounding counties and states sent their troubled children to the small campus, billed as a “therapeutic boarding school,” in the foothills of the Catskills.

Upon arrival, the children were strip-searched in front of other students, and an adult watched as they rubbed lice shampoo into their hair and genitals in a shower, according to testimony. They were assigned to a “family,” with staff members playing the role of parents.

Mr. Geer, who taught at the school from the early ’90s until it closed in 2014, was the “father” of Family Six. He openly described himself to students as a sex addict who hit rock bottom while driving one day and nearly crashing as he masturbated, former students testified. “This constant, returning story,” Steve Zahoroiko, 43, a former student and, later, a marine, testified. “That was the shining moment in his life, when he turned everything around.”

He forced students to admit to impure thoughts and actions in front of their new family. “Talk about whatever sex lives we supposedly had,” Mr. Zahoroiko said.

Mr. Geer was repeatedly described as flying into a rage when confronting a student. “Being screamed at by him very close to my face,” Ms. Boysick testified. “Red-faced, sweating.”

Other students recalled being forced to run in place all day — “trotting” — or haul buckets of rocks up and down a hill as a punishment.

Prosecutors called several former students who said they were sexually abused by Mr. Geer. A 39-year-old man identified as “Victim 3” testified that he had been forced by Mr. Geer to join the choir — “I wasn’t a singer” — and that the teacher had abused him on a school trip to Toronto, in a hotel room. Prosecutors showed videos of his singing in the choir, a younger Mr. Geer energetically conducting the group.

“Never thought I’d be up here on the witness stand talking about this, ever again,” the former student testified. “But he was the devil.”

Mike Milia, 46, another former student, testified that Mr. Geer took him on a fishing and sightseeing trip to Maine for several days in 1994, when he was 15. His parents did not know about the trip. Prosecutors showed photographs of the smiling teenager posing before roadside signs — “Brake for Moose.”

“We never put a fishing rod in the water,” Mr. Milia testified. Instead, Mr. Geer bought beer and pornographic magazines and sexually abused the teen for days, he testified.

Mr. Geer’s lawyers with the federal public defenders’ office sought to soften the grim portrayal of the man and the school. A former administrator, Emmanuel “Mike” Argiros — a son of the founders — testified that he had never heard complaints about Mr. Geer abusing children, and that he had sent three of his own children to the school, in part for its excellent music program.

Former students were confronted with smiling yearbook photographs of their teenage selves, paired with glowing testimonials about their time there. Mr. Zahoroiko, the former marine, chuckled on the witness stand and said the students did not write those blurbs; the school did.

Defense lawyers have raised inconsistencies in the students’ versions of events over the years, in F.B.I. interviews and elsewhere. Elizabeth Ianelli, a former student and an organizer of the earliest public attacks against the school, wrote a memoir of her time there, “I See You, Survivor,” published in 2023.

But she was called as a witness for the defense on Wednesday, and lawyers raised contradictions between what she had written and what she testified.

Throughout, Mr. Geer watched in silence, occasionally wincing in apparent physical pain and seeming to have difficulty rising from his chair when jurors entered or left the courtroom.

Lauren LaCroix, 34, flew to Albany from San Diego, where she lives with her husband and young sons, to watch the trial. She had tried to put her time at the school behind her. Now, she found comfort in meeting other former students.

“There’s no explaining,” she said. “They get it right away.”

Listening to accounts of abuse, she thought of a female staff member who had pulled her aside shortly after her arrival at the school. “She said, ‘I never want you alone with Paul Geer,’” Ms. LaCroix recalled.

On Monday, after an afternoon and a following morning of deliberations, the jurors returned with its verdict.

Guilty on the two counts involving the choir singer in Toronto.

Guilty on the two counts for Mr. Milia on the road trip to Maine.

But jurors were unable to reach a verdict on the counts related to Ms. Boysick — the only counts without photographs to document her time with Mr. Geer.

To those in the audience, Mr. Geer appeared to tear up with emotion at the verdict. He was led away in handcuffs, to remain in jail until his sentencing in July.

Ms. Boysick, who was among the first students to publicly come forward, using her name in a lawsuit, felt vindication, not loss, in the verdict, despite the outcome of the counts involving her.

“I’m going to totally own those guilty verdicts,” she said. “It wouldn’t have happened if it wasn’t for me.”

She said that moments before the verdict, Mr. Geer looked at her — “Wide-eyed, pure fear, what’s about to happen to me?” she said.

It was a feeling Ms. Boysick and her old classmates in the gallery once knew well.

When one of New York City’s most prestigious private schools hired Winston Nguyen in 2020, administrators knew about the felony conviction for fraud in his troubled past. But the second chance they offered him backfired. Nearly four years later, Mr. Nguyen, a math teacher, was arrested again, accused of preying on students. And the school, Saint Ann’s in Brooklyn, faced a roiling crisis.

On Monday, Mr. Nguyen, 38, pleaded guilty to a felony and several misdemeanors after being charged with soliciting lewd images and videos from students. When he is sentenced later this month, he faces a possible seven-year prison term.

Mr. Nguyen was taken into custody after the hearing and will be held temporarily at the Rikers Island jail complex.

His plea marks the latest chapter in a scandal that has marred the reputation of Saint Ann’s School and the administrators who hired him.

This is the second time Mr. Nguyen has been convicted of a felony. In 2019, he pleaded guilty to grand larceny and other charges after he was accused of stealing more than $300,000 from his employers, an older couple he worked for as a home health aide.

He served four months at Rikers, and about a year later was hired by Saint Ann’s, a school that charges about $60,000 per year in tuition and caters to New York’s wealthy creative class.

A nattily dressed figure who arrived at class often in a suit and sometimes with a bow tie, Mr. Nguyen transformed a felony record from a liability into a résumé-builder at a school known for embracing unconventional educators. He taught a seminar called “Crime and Punishment” and quickly become a fixture at the school.

It was the kind of opportunity that few felons get.

In interviews with The New York Times last week, Mr. Nguyen tried to make sense of how he squandered it all, and how he plummeted from the promise of his youth — a driven high school student, he was once honored by the mayor of Houston, his hometown, and went on to attend Columbia University — to the reality of being a 38-year-old man headed to prison for the second time in six years.

“I’ve hurt so many people,” he said.

Mr. Nguyen declined to directly address the students he targeted — he will do so when he is sentenced, he said — but expressed remorse for the damage he caused to the school. “It was an incredibly great community to me, and I really, really regret that my actions have painted them in a horrible light,” he said.

Neither the students targeted by Mr. Nguyen nor their families have spoken publicly, and prosecutors have protected their privacy through the legal process.

Sitting in the courtyard outside his Harlem apartment, Mr. Nguyen vacillated between teary recognition of his transgressions and occasional intense bursts of self-analysis. He said he suffers from a mental illness, bipolar II disorder, which he said went untreated during the Covid-19 pandemic, and that he experienced sexual abuse as a child, but he did not make excuses for his behavior. “I very much take responsibility for my actions,” he said. “I made bad decisions.”

In Brooklyn criminal court on Monday, Mr. Nguyen arrived 30 minutes late, wearing an untucked T-shirt, casual slacks and a parka. He carried a large red shopping bag and a large red book, The New Oxford Annotated Bible.

Mr. Nguyen agreed to plead guilty to one count of using a child in a sexual performance and five separate counts, representing five children, of “knowingly acting in a manner likely to be injurious to the physical, mental or moral welfare of a child less than 17 years.”

Daniel Newcombe, an assistant district attorney, informed the judge of the recommended punishment: seven years in prison, 10 years supervision after his release and a requirement that he register as a sex offender for 20 years.

Mr. Nguyen’s sentencing will take place in two weeks.

The judge, Philip V. Tisne, asked Mr. Nguyen if he understood that after the completion of this sentence, should he be convicted of a felony a third time, he would automatically be sentenced to 25 years to life in prison.

“Yes, your honor,” Mr. Nguyen said.

Eric Gonzalez, the Brooklyn district attorney, said the plea agreement held Mr. Nguyen responsible for his “disturbing and predatory conduct” while sparing victims from having to testify.

When the hearing ended, court officers cuffed Mr. Nguyen’s hands behind his back. He slung his head downward as his lawyer, Frank Rothman, patted his back. He was led out a side door.

Outside the courtroom, Mr. Rothman was circled by reporters. “There is no defense one can proffer when you have images on your phone,” he said.

“I don’t know what his first night is going to be like,” Mr. Rothman said. “I’m sure he is anxious. He is going to jail as a sex offender.”

Mr. Nguyen was hired as an administrative aide at Saint Ann’s in the summer of 2020. He had alerted the administrator who interviewed him that he had been convicted of a felony, and at least one Saint Ann’s employee urged the school’s leaders not to hire him.

He quickly became an indispensable member of the staff, helping to manage logistics during the pandemic as he integrated himself into the school community.

The school promoted Mr. Nguyen to math teacher in the fall of 2021 but did not alert parents to his criminal record until after students discovered news stories about him on the internet. In October of 2021, Vince Tompkins, then the head of the school, sent parents an email about the new math teacher. “I can assure you that as with any teacher we hire, we are confident in Winston’s ability and fitness to educate and care for our students,” he wrote.

Within a year, students at Saint Ann’s and other Brooklyn private schools — some as young as 13 — began to receive solicitations via Snapchat for lewd photos and videos. The user behind the anonymous Snapchat accounts sent one student a graphic video of a 16-year-old boy masturbating.

By February 2024, Saint Ann’s had been notified by the Brooklyn district attorney’s office that it was investigating the continued targeting of its students by anonymous Snapchat accounts seeking sexual photographs and videos. School administrators did not notify parents.

Days before the end of the school year, Mr. Nguyen was arrested near Saint Ann’s. He was charged in July with 11 felony counts, including using a child in a sexual performance, promoting a sexual performance by a child and disseminating indecent material to a minor.

The news shocked parents and students and led to a torrent of media coverage.

In December, Saint Ann’s released the findings of an investigation conducted by lawyers commissioned by the school’s board to determine how the school had come to employ a felon.

The blistering report said that the school administration had “shamed” parents who expressed concern about Mr. Nguyen’s background and had suggested they were not in step with the school’s progressive values.

“In some instances,” the report said, administrators “prioritized teachers including Nguyen over the concerns of students and their families about the teacher’s background or behavior.”

In the months since his arrest, Mr. Nguyen mostly has been confined to his apartment. He takes part in video therapy sessions, including group sessions with other people accused of sexual offenses, and has attended occasional church services. Otherwise, he has remained isolated, reading and watching television.

His sister recently visited him from Houston to help him clean out his apartment as he prepares to grow into middle age in prison. “I don’t deserve the family that I have,” Mr. Nguyen said.

In recent weeks he has been culling his belongings. While packing, he came across a warm coat given to him during a cold winter by Bernard Stoll, the man he worked for and stole from before his employment at Saint Ann’s. “People have been very, incredibly good to me, and I betrayed their trust in a very deep way,” he said.

He did not wish to stand trial, he said.

“I am at a place where I know what I’ve done,” he said. “I think part of the reason I feel so horribly is I just don’t know any way I can make it better for the kids, or for their families or for the school. I accept this sentence because I know that I did something wrong and I want to answer for it.”