Ms Redding was 13 when the search incident happened

The US Supreme Court has ruled that school staff broke the law when they ordered a 13-year-old girl to strip while searching her for painkillers.

The Arizona school, which bans prescription and over-the-counter drugs, suspected Savana Redding, then 13, of carrying ibuprofen.

After no drugs were found in her bag, she had to remove her clothing, and then move her bra and underwear.

However, the court said individuals could not be held liable in a lawsuit.

The school principal acted on a tip-off from another student that Savana was carrying ibuprofen.

Justice David Souter said: "What was missing from the suspected facts that pointed to Savana was any indication of danger to the students from the power of the drugs or their quantity, and any reason to suppose that Savana was carrying pills in her underwear," Associated Press reported.

"We think that the combination of these deficiencies was fatal to finding the search reasonable."

The justices said the lower courts would have to determine whether Safford United School District No. 1 could be held liable.