A former Amherst College student is just the latest in a long line of men whose lives have been turned upside-down after being accused of sexual assault in what they say were consensual encounters, punished in campus tribunals where, in some cases, critics say, they’re guilty even after proving their innocence.

The former student, whose name has not been made public, was expelled after his alleged victim, the roommate of his girlfriend, complained some 21 months after the incident and despite what evidence appears to show was consensual sex. As in many campus procedures which enforce school sanctions and not criminal law, only a finding that he was “more likely than not” guilty was necessary.

“Essentially the procedure there works under the assumption that the accused is guilty and needs to use the hearing to prove his innocence,” K.C. Johnson, author of “Until Proven Innocent: Political Correctness and the Shameful Injustice of the Duke Lacrosse Rape Case," told Fox News Channel's Megyn Kelly. “But he isn’t given the tools to do that. He doesn’t have discovery, he can’t get the relevant evidence he needs, he doesn’t have an attorney representing him [and has] limited right of cross examination.

"So there’s virtually no way, once an accusation is made and gets into the system at a place like Amherst, and Amherst is not unique, that the accused can be exonerated,” Johnson said.

“Essentially the procedure there works under the assumption that the accused is guilty and needs to use the hearing to prove his innocence.”

- K.C. Johnson, author of book on Duke lacrosse case

Johnson, a history professor at Brooklyn College, said many schools adopted similar standards after a 2011 edict from the Obama administration, which claims 1 out of every 5 women in college is the victim of a sexual assault. In what became known as the “Dear Colleague” letter, the federal Department of Education warned that schools that do not crack down on sexual assaults could lose federal funding.

In the Amherst case, the expelled student’s attorney is suing the school in federal court, where traditional rules of evidence have produced incriminating text messages sent by the alleged victim that appear to indicate she not only consented to, but initiated the sex. His attorney also alleges that the woman told campus investigators the sex began consensually, but that she revoked her consent during the act.

The suit seeks $75,000 and names the school, President Carolyn Martin and several officials for moving “with enormous speed to expel John Doe, eject him from the campus, and destroy his reputation.”

Other cases in which young men’s lives have been damaged by accusations that might not stand up in a traditional court have made recent headlines.

Paul Nungesser, a Columbia University student accused of raping fellow student Emma Sulkowicz, is suing the Ivy League school for allowing Sulkowicz to conduct a campaign against him that includes dragging a mattress around campus and making a video re-enactment of her alleged rape. Unlike in the Amherst case, Nungesser was cleared of rape charges, yet the school did nothing to stop Sulkowicz from harassing him, according to a federal suit. The mattress campaign was even sanctioned by a professor as her senior visual arts class project.

Nungesser’s federal lawsuit alleges the school, by not stopping Sulkowicz, "effectively destroyed" his college experience, reputation and future career prospects.

 Another Ivy League case involves Brown University student Daniel Kopin, who was accused in 2013 of sexually assaulting an ex-girlfriend and fellow classmate, Lena Sclove, months earlier. Kopin claimed the sex was consensual; Sclove, in a formal complaint with Brown’s disciplinary board, said she had been raped.

Kopin was charged with four violations of the student code of conduct, suspended for the rest of the year and told he would have to apply for readmission. Up to that point, his name had been kept private, but Sclove balked at the sanction, saying she was threatened by Kopin’s possible return to campus. After she hosted a press conference, the school’s Daily Herald outed Kopin.

Kopin is also suing the school in federal court, and these cases are among more than 20 filed in recent years against schools by defendants who say they were illegally punished for sexual assaults they never committed.

In some cases, criminal investigations conducted outside of campus have shown the alleged attackers to be innocent. Caleb Warner, a onetime student at University of North Dakota, was charged in 2010 with sexually assaulting a fellow student in what he insisted was a consensual encounter. He was found guilty by a campus tribunal and expelled, but months later, local police charged his alleged victim had deliberately falsified the charges. She was charged with lying to police, and fled the state.

While no one doubts that sexual assault occurs on campuses and is a problem, Christina Hoff Sommers, a resident scholar at the American Enterprise Institute and author of “The War Against Boys,” says the so-called “rape culture” on campus is exaggerated, and the lines between consensual sex that is later regretted and actual assault is being blurred. A complaint is often enough to get the accused thrown out of school, she said.

"In an American courtroom, those accused of crimes have a right to a lawyer, a right to question accusers, and they are presumed innocent until proven guilty," Sommers told FoxNews.com. "It’s all reversed in today’s campus rape tribunals."

Sommers says the real number of college women who are victims of sexual assaults that would measure up to the standards of a criminal court is about 1 in 40. She said the 1-in-5 figure cited by the administration includes verbal threats and is derived from surveys in which respondents are asked “an artful combination of straightforward and leading questions” and categorize all sex that occurs while the female is intoxicated as rape.

Despite the lawsuits brought by male students who say they were wrongly accused, the Department of Education is maintaining pressure on schools to vigorously investigate and prosecute claims of alleged assault victims or possibly face federal funding cuts. In April of 2014, the White House Task Force to Protect Students from Sexual Assault issued a report urging schools to do more.

“Colleges and universities can no longer turn a blind eye or pretend rape and sexual assault doesn’t occur on their campuses,” Vice President Biden said as the report was released. “We need to provide survivors with more support and we need to bring perpetrators to more justice and we need colleges and universities to step up.”

Days later, the Department of Education named 55 schools that were under investigation for their treatment of rape allegations, including universities such as Harvard and Dartmouth.

Sommers said the threat of funding cuts has gotten the attention of schools, who 

"University and college officials were terrified of running afoul of the new  version of Title IX mandated by the Department of Education in 2011," Sommers said. "So they are quietly amending the U.S. Constitution.

"The First Amendment is now being replaced by a woman’s right not to be made uncomfortable," she added. "Due process is being treated as a barrier to justice -- rather than its essence."