The Supreme Court has long struggled to balance the privacy rights of students against schools’ need to keep campuses safe. On Tuesday, the court hears arguments in a suit brought on behalf of a 13-year-old girl who was strip-searched based on a fellow student’s false report that she had possessed ibuprofen pain-relief pills.

The invasion of privacy was extreme and the security rationale weak. The court should rule, as a lower appellate court did, that the search was unconstitutional.

Savana Redding was an honors student at a middle school in Safford, Ariz., with a clean discipline record. A friend of Savana’s, who was found in possession of pain relievers, told school authorities that Savana had given her 400-milligram ibuprofen pills, a prescription-level dose of the pain reliever in over-the-counter Advil and Motrin, used to treat headaches and menstrual cramps.

Based on this information, a male assistant principal had Savana taken out of class and strip-searched by two female employees. Savana was told to pull her bra in a way that exposed her breasts, and to pull out her underwear to expose her pelvic area. Savana, who was too scared to refuse, later called the search “the most humiliating experience” in her life. No drugs were found.

Savana’s mother sued the school district, charging that her daughter’s Fourth Amendment rights had been violated.

The Supreme Court has held that to satisfy the Fourth Amendment, a search of a student by school officials must be reasonable at the start. The search of Savana was not. It was based entirely on the self-serving statement of a student who was trying to deflect blame from herself. The school did not corroborate the tip before acting and the student who gave it did not say that Savana currently had ibuprofen, or that she was hiding it in a place where a strip search would be needed to find it.

The Supreme Court has also said that a search of a student must be reasonable in scope, taking into account the circumstances.

Again, the search of Savana fell short. As the San Francisco-based United States Court of Appeals for the Ninth Circuit observed, it is “common sense” that telling a 13-year-old girl to disrobe to partially reveal her breasts and pelvis because she might possess ibuprofen — “an infraction that poses imminent danger to no one” — was unreasonable. The school could, the court pointed out, simply have kept Savana in the principal’s office until a parent arrived.

With many communities today worried about keeping drugs and other contraband out of schools, the Supreme Court may be tempted to focus on schools’ need to enforce their rules. The court may also be reluctant to hold schools liable for damages for improper searches, given how tight budgets are right now.

These are important concerns, but so — as the founders made clear in the Fourth Amendment — is the right of every American to be free from unreasonable searches. The strip-search of Savana was unnecessary, humiliating and clearly unreasonable.