(Reuters) - Australia's High Court onWednesday backed the broadcasting watchdog's finding that anAustralian radio station broke the law with a prank call to aBritish hospital taking care of the pregnant Duchess ofCambridge, paving the way for penalties.

Two presenters at Sydney's 2Day FM called the Londonhospital in December 2012, pretending to be Queen Elizabeth andPrince Charles.

They were put through to a nurse who disclosed details ofCharles' daughter-in-law's condition during treatment for severemorning sickness in the early stages of pregnancy, makingheadlines around the world.

The nurse who answered and transferred the call committedsuicide three days later.

On Wednesday, the High Court in Canberra ruled in favour ofthe Australian Communications and Media Authority (ACMA),overturning a ruling by the lower Federal Court.

The earlier ruling said the watchdog did not have the powerto find 2Day FM broke the law because it did not have authorityin criminal matters.

The High Court said ACMA did have the power to determine thestation had committed a criminal offence, as a preliminary totaking enforcement action under the Broadcasting Services Act.

ACMA did not immediately return calls seeking comment.

In its ruling, the High Court said the station did notobtain the consent of the hospital's staff to air the recordingof the call.

The two presenters, Mel Greig and Michael Christian, bothapologised for their actions in the wake of the scandal and saidthey were devastated by the death of Indian-born nurse JacinthaSaldanha, 46. Greig attended the inquest into Saldanha's deathat London's High Court. (Reporting by Jane Wardell; Editing by Clarence Fernandez)