It's not good for teachers to have sex with students in high school under any circumstances. On that we can all agree.

But in seeking to clarify a law making it a crime for a teacher to have sex with an 18-year-old, the Washington Education Association appears to be doing a better job of further confusing the issue.

The union has filed a "friend of the court" brief in a case involving a Grays Harbor County teacher accused of having sex with an 18-year-old female student. The defense challenged the statute, saying a student who is 18 is considered an adult, therefore a teacher can't be charged with sexual misconduct with a minor.

WEA's contention is that the law is vague and should be clarified as to whether the intent is to cover all students or just students who are minors. Yet filing a brief on behalf of a defendant at least gives the appearance of not only taking sides, but playing a game of semantics.

The law is vague. But why doesn't WEA move to clarify it in the Legislature, rather than taking sides in a lawsuit to protect a teacher accused of serious misconduct?

The defense appealed a Grays Harbor Superior Court ruling last year that the law was clear and a student can be a victim of the crime even if he or she is 18. Oral arguments in that case were heard Tuesday by a state appeals court.

To further muddy the legal waters, last month a Benton County Superior Court judge said the law is too vague as to what constitutes a minor in such situations and dismissed the charge against a former Richland High School music teacher accused of having sex with an 18-year-old student.

Such conflicting court interpretations alone signal the need for a legislative remedy. But let's make no mistake what the issue is that should be clarified: No teacher should have sexual contact with any student of any age through high school. Period, no exceptions. Teachers at that level simply are in a position to impose too much influence on impressionable students.

Beyond high school it's different, and the legal age of 18 is a legitimate plateau to be treated as an adult.

A spokesman for WEA said the union does not condone teachers having inappropriate sexual relationships with students of any age.

"Filing this brief should not be construed to mean that anybody within WEA condones inappropriate sexual conduct with students," Rich Wood, a spokesman for the union told the Tri-City Herald. "... It would be an insult to suggest our 81,000 members would condone that kind of behavior. They don't."

But WEA officials, by intervening in the case, appear to be revealing a bias and rush to protect a teacher under fire rather than using common sense. The union could have come out strongly for clarification of the law without becoming part of the court proceedings.

Any teacher guilty of that kind of sexual misconduct with any student should be banned from the teaching profession. It really doesn't matter if the student involved is 17 years and 11 months old or 18. And conviction should be treated as a criminal offense.

The law should be clarified to reflect that. On that we can agree with the teachers union.

* Members of the Yakima Herald-Republic editorial board are Michael Shepard, Sarah Jenkins, Bill Lee and Karen Troianello.