Commonwealth Court Judge Kevin Brobson cleared the way this week for the Pennsylvania Interscholastic Athletic Association to end a dangerous trend. It should follow through.

Judge Brobson said a 1975 court ruling allowing girls in Pennsylvania to play on boys' sports teams does not necessarily preclude the PIAA from keeping boys off of girls' teams. If the PIAA, which is charged by the Legislature with administering high school sports, finds it is good public policy to ban boys from girls' teams, it is free to adopt the appropriate rule. If that rule is challenged, the court then would come into play.

Statewide, some schools bar boys from playing on girls' teams, while others allow it. The PIAA should standardize a ban on the practice.

Some people - including, remarkably, state Attorney General Kathleen Kane - argue that such a ban constitutes gender-based discrimination, but that is disingenuous and contrary to the reasons that federal law has established equal opportunity for girls in sports and the classroom.

Girls' teams exist so that girls will have the same opportunity as boys to participate in varsity sports, not only for the sake of the experience, but for the chance to compete for scholarships and other benefits that always have been open to boys.

The spectacle of allowing boys to play girls' sports while otherwise eligible girls are forced to the sidelines is perverse. It makes a mockery of the notion of fair competition. There are vast physical differences between freshmen and seniors even when girls play against girls and boys play against boys. Where is the fairness in a senior boy competing against a freshman girl?

The PIAA is correct to worry about competitive balance and safety. It noted that in last year's state cross-country championships, 505 of the 674 boys who ran finished ahead of the first of 663 girls.

In volleyball, girls' nets are lower than boys' nets for obvious reasons. Yet PIAA General Counsel Alan Boynton told the Associated Press that the agency is aware one girls' team that will have as many as six boys playing this year. Increasing numbers of boys also are competing in girls' field hockey, swimming, soccer and tennis.

The PIAA should work to build consensus for a ban and the implement it so that fair competition won't be mocked for the sake of false equivalence.