Schools can prevent students from wearing clothes with messages thought to demean or impinge on the rights of others, despite arguments that barring a student from certain expression violates the constitutional right of free speech, a federal appeals court ruled Thursday.

The federal case stems from a situation in which a Poway teen sued his school district after it barred him from wearing a T-shirt with anti-gay statements and biblical messages taped on it.

Most of the suit is still at the federal trial level, but Tyler Chase Harper appealed to the higher court on the sole issue of the trial judge's refusal to bar the school from enforcing its dress code.

In a 2-1 ruling, a panel of judges on the 9th District U.S. Court of Appeals sided with the Poway Unified School District, finding that while certain speech is protected outside of a public school, it is not necessarily protected on school grounds.

The Supreme Court decided in the 1960s that students don't shed their First Amendment rights when they come to school, but has also ruled that there are limitations to expression on school grounds.

On Thursday, a law group that fights for religious freedom released a statement that they plan to appeal what it called the "extremely poor ruling" to the entire 9th Circuit.

Thursday's ruling sets binding law on federal trial courts in the 9th Circuit, which includes the West Coast states, Hawaii and Alaska.

Harper, now a senior, was a sophomore at Poway High School in April 2004 when he wore to school a T-shirt with anti-gay statements and biblical messages written on masking tape. On the tape was the phrase, "Homosexuality is shameful" and a reference to a Bible verse that addresses the topic.

The teen first wore the messages on a day that a campus group staged an event called "Day of Silence" to promote tolerance of homosexual, bisexual and transgendered students. A year earlier, in 2003, the annual "Day of Silence" event led to altercations on the campus.

On the day following the 2004 event, when Harper again wore similar messages condemning homosexuality taped to his shirt, a teacher sent him to the principal's office because other students in the class were distracted by the shirt. Harper refused to remove the statements and was prevented by administrators from returning to class that day. He was not suspended.

Two months later, the teenager sued in federal court in San Diego, arguing that the school violated his constitutional rights, including the rights to free speech and religious freedoms. As part of that suit, Harper asked that the school district be barred from enforcing its dress code.

Thursday's opinion addresses only the narrow issue of the dress code. However, in the ruling, two of the judge's noted that Harper is not likely to succeed in his case.

Judge Stephen Reinhardt wrote the 54-page opinion, joined by Judge Sydney Thomas.

The two judges found that the school can prohibit Harper from wearing the anti-gay messages because the messages impinge on the rights of others, that public school students "have a right to be free of such attacks while on school campuses."

"The school had a valid and lawful basis for restricting Harper's wearing of the T-shirt on the ground that his conduct was injurious to gay and lesbian students and interfered with their right to learn," Reinhardt wrote.

The judges also said the school was not discriminating against Harper point of view, nor was denying him from wearing the shirt a "substantial burden" on his right to religious freedoms.

Attorney Jack Sleeth, who represents the school district, said his clients' reaction to the ruling "has been positive."

"They have a feeling of satisfaction that the court recognized they were trying to do the right thing," Sleeth said.

Judge Alex Kozinski, the third judge on the panel, wrote a strongly worded dissent.

"I have considerable difficulty with giving school authorities the power to decide that only one side of a controversial topic may be discussed in the school environment because the opposing point of view is too extreme or demeaning," Kozinski wrote.

He also said the ruling had "no anchor in the law" and is "entirely a judicial creation, hatched to deal with the situation before us, but likely to cause innumerable problems in the future."

Robert Tyler, who represents the teenager, on Thursday called the court ruling "political correctness cloaked under the veil of tolerance" and said it "reflects judicial activism."

"The majority opinion decided to stray from precedent and establish new law," Tyler said.

Tyler said he isn't sure if he will appeal the ruling until after the case concludes at the trial court level, or appeal sooner --- but indicated that he will appeal.

"These cases aren't decided until they breathe their last breath," Tyler said, "and there is still a lot of oxygen."

When he took the case, Tyler was a staff attorney with the Alliance Defense Fund, which takes on religious freedom cases. He is now with a group called Advocates for Faith and Freedom.

On Thursday, Alliance Defense Fund officials released a statement that they plan to appeal what it called the "extremely poor ruling" to the entire 9th Circuit.

To read the opinions, go to www.ce9.uscourts.gov/ and click on the link to the 9th Circuit Court of Appeals' Web site.

Contact staff writer Teri Figueroa at (760) 631-6624 or tfigueroa@nctimes.com.