A debt ridden army officer was encouraged by an advert to sell information to The Sun a court was told today.

John Hardy, who is on trial for committing misconduct in a public office, admitted selling the newspaper information on Princes Harry and William while he was an instructor at Sandhurst, but said when he saw an advertisement in The Sun asking for officers and cadets to phone the paper with stories he thought that it must be legal. "You can't believe a major corporation would be encouraging people to commit a crime" he said, adding that the army, the Ministry of Defence and even the Prime Minister must have seen the advert yet "it hadn't been stopped”.

The former soldier told the court that after 16 years in the army his salary was still only £24,000 a year and after deductions only took home around £1600 a month. He had a young child to support and had been forced to take on a second job, guarding the Daily Mail building overnight. He had also been affected by the death of fellow soldiers in Afghanistan, had begun to "drink heavily" and had got into debt. He said he had contacted The Sun's newsroom and been told by their legal department that he would not be committing a crime by passing on information about the Princes, so he decided to go ahead.

Standing trial alongside Hardy are his wife Claire, Sun Royal editor Duncan Larcombe, deputy editor Geoffrey Webster, executive editor Fergus Shanahan and former chief reporter John Kay. All are facing charges relating to a series of payments to Hardy and a Ministry of Defence civil servant, Bettina Jordan-Barber, for the prosecution allege, confidential army information including details of military casualties in Iraq and Afghanistan.

Amongst the information allegedly supplied by Hardy to The Sun was a picture of Prince William in a bikini at a fancy dress party and another with him dressed as a "chav". He also supplied details of the princes' training regime and on one occasion received a £250 "sub" from the paper so he could attend a strip club with other Sandhurst instructors and inform The Sun what happened. "It was the easiest money I ever made in my life" the defendant said.

All of the defendants deny all of the charges, the trial continues.