Sexual liaisons on campus will not go away despite the best of intentions.

With good reason probably, there is a growing trend of American universities setting new standards about “sexual liaisons” between faculty members and students, primarily undergraduates who are likely to be “adult,” 18 but not yet 21 years old. The distinction is difficult to discern because young people can vote and enter the nation’s armed forces at 18 but can’t buy liquor in many places until they are 21.

At any rate, Virginia’s College of William and Mary has officially banned all sexual contacts between professors and undergraduates. The barrier includes faculty and graduate students who are under their supervision. The latter category was established because many faculty members and graduate students might be near the same age levels.

Stanford University has heightened its policy to require professors to give up “any supervisory or evaluative function” over their campus romantic partners. They are to report such relationships to their department chairs or deans. Ohio Wesleyan University bars faculty people from any romances with students they supervise, advise or evaluate.

But it will take massive supervision and a lot of luck to eliminate, or even trim perceptibly, relationships between faculty and students, no matter where the college might be.

That in mind, many schools have done little or nothing about re-ordering regulations. They realize that people will be people, at any age or academic level and that there is no fail-safe resolution.

Parents, naturally, are eager to know their youngsters, male or female, will not be preyed upon by lascivious teachers. Students who might have been approached by faculty people call for protection. Teachers who might be “stalked” by eager students also need coverage from false charges.

Such situations have existed for centuries and will be around long after all of us are gone. Things can get ugly; Kansas University not too long ago ousted one professor because of his conduct with female students.

University people want an approach to the touchy subject that is “enforceable, makes sense and is not so prohibitive as to drive the issue underground,” said Laraine T. Zappert, director of the Stanford Sexual Harassment Policy Office.

“It’s professionally dumb to be grading someone you’re having a romantic relationship with,” Zappert added. “It just defies any sense of fairness to the person or anyone else.”

Unfortunately, humans continue to ignore Zappert’s common-sense advice and university officials continue to struggle with policies to monitor this behavior. It’s too bad that adults can’t practice the proper level of responsibility and control to avoid these problems.