The free-speech case tests the limits of student messages officials could try to suppress.

Joseph Frederick, then 18, unveiled the 14-foot paper sign on a public sidewalk outside his Juneau, Alaska, high school. Principal Deborah Morse confiscated it and later suspended the young man.

At issue was whether Frederick’s free-speech rights were violated and the discretion schools should be allowed to limit messages that appear to advocate illegal drug use.

“Bong,” as noted in the appeal filed with the justices, “is a slang term for drug paraphernalia.”

“It was completely disruptive of the message, of the theme that the school wanted to promote,” said Justice Anthony Kennedy, in support of the school.

Justice David Souter expressed some concern. “It’s political speech, it seems to me,” he said. “I don’t see what it disrupts, unless disruption simply means any statement of disagreement with a position officially adopted by the school.”

The incident occurred in January 2002 just outside school grounds when the Olympic torch relay was moving through the Alaska capital on its way to the Salt Lake City, Utah, Winter Games.

Though he was standing on a public sidewalk, the school argues Frederick was part of a school-sanctioned event, because students were let out of classes and accompanied by their teachers.

Morse ordered the senior to take down the sign, but he refused. That led to a 10-day suspension for violating a school policy on promoting illegal drug use.