As classes begin at colleges and universities across the country, incoming and returning students need to be keenly aware of the current culture surrounding sex on and off campus.

First and foremost, students can assume that they have no constitutional due process rights on their college campus, even in public institutions. One might think that they do, as those rights are guaranteed under the Constitution, but the truth today is that when you step foot on that campus you live by their rules.

That is because college campuses are now responsible for their own criminal justice system, thanks to an interpretation of a federal law. While colleges would never be expected to adjudicate a murder, they are now expected to adjudicate accusations of sexual assault. And the marching orders from Washington suggest that the goal of such adjudications should be to punish accused students, truth be damned.

And these campuses are not bound by the presumption of innocence or the rules of evidence or any other basic legal concepts. These days, an accusation almost ensures a finding of guilt and an expulsion. And the evidence used to justify the expulsion is becoming flimsier and flimsier.

For example, a student using the pseudonym John Doe was expelled from Amherst College based on an accusation made nearly two years after the alleged incident. That was enough to expel him, and despite his lawyer discovering text messages sent from the accuser immediately after the encounter that cast serious doubt on her testimony, the school refused to reinstate Doe.

The fact is that an accused student relinquishes his rights and his reputation. That was the case for Paul Nungesser of Columbia University, who despite being found not responsible (four times from four accusations made by four friends), was subjected to harassment on campus and in the media. He is now suing.

Here's my best advice as someone who's been following campus sexual assault for a while: Once you're accused, retain a lawyer (obviously this means poorer students are at an immediate disadvantage). But remember, that lawyer will most likely not be able to speak during the campus hearing or effectively represent you — they're there as outside counsel. Schools compel testimony from accused students by threatening to continue an investigation without the accused student's side of the story if they refuse to speak. And once an accused student speaks to campus administrators, whatever they say can eventually be turned over to the police, providing a path around the Miranda warning.

And forget evidence. Accused students across the country have had their evidence (such as friendly text messages before and after an encounter) discounted or worse, used as evidence against them.

One might think this means it is only casual hookups that may lead to an accusation of assault. Wrong. Even committed relationships — should that relationship end — can be fodder for accusations.

Former Auburn University student Joshua Strange was accused of sexual assault even though he stopped when his girlfriend asked him. She called the cops on him but apologized for her behavior and continued to date Strange. Two months later they broke up, and she accused him of assaulting her in a parking lot (miles away from where he was at the time). She then reported the sexual assault to campus administrators, and he was expelled. Again, this was a campus accusation that arose after a breakup.

And it's not just heterosexual couples who are at risk. At Brandeis, two men dated for nearly two years, but after the breakup (and after the accused began seeing someone else) the accuser claimed sexual assault throughout the entire relationship. Because the accuser had not given clear, verbal consent on the first night the pair slept together, the accused was deemed to have committed sexual assault. It didn't matter that after that first encounter the two dated for 21 months; all that mattered was that specific encounter.

The accused in that case was also found responsible for sexual assault because he would often wake his partner up with a kiss — and since one cannot consent while asleep, those kisses (again, between two people in a committed relationship) constituted sexual assault.

Such normal human interaction is now being redefined as sexual assault and it comes from the adoption of "yes means yes" policies by many schools. These policies define nearly all sex as rape, as sex now must be conducted as a question-and-answer session to ensure consent was obtained. And if the accuser had any alcohol, consent is negated — in some cases any amount of alcohol, not just an incapacitating amount — is enough to expel an accused student.

You might be reading this and thinking: "You're crazy, Ashe. Stop being so dramatic!" But one needs only to click on any of the links provided above to see that the situation on college campuses these days is dire.

Students, especially male students, need to stop viewing sex merely as pleasure or as an expression of affection or love, and begin seeing it as a potentially life-ruining moment. And as someone who has never advocated abstinence, that is a painful thing to have to say.

The situation has gotten so bad that one parents' group has begun distributing flyers on California campuses warning students of how easy it is to be accused and expelled.

The reality of it is this: There is little trust anymore between the sexes. Women are being told that men, especially men they believe are their friends, are waiting to get them drunk and rape them. This in turn is leading men to believe that women are going to accuse them of sexual assault for just about any reason, even for consensual sexual encounters.