There could have been other sources for stories for which police officers and an NHS worker were paid by The Sun, the paper's former news editor Ben O'Driscoll told a court today.

Giving evidence at The Sun corruption trial, Mr O'Driscoll said that although he "assumed" district reporter Jamie Pyatt had a source inside Broadmoor high-security hospital, other people such as local people residents might know what was happening there.

He told Kingston Crown Court that Mr Pyatt's reference to a "police contact" in an email could have meant "anything."

Mr O'Driscoll, now deputy news editor at the Daily Mail, said he would not rely on what reporters told him about their sources, but rather wait for confirmation of their stories from official sources.

Tips from drivers of black cabs were often just as likely to be true as stories from reporters claiming to have inside information, he said.

Cross-examining, Oliver Glasgow, for the Crown, suggested that the newsdesk would want to know the provenance of a story – and its accuracy – before putting it forward to the editor at the morning editorial conference.

He asked: "The editor asks you questions and he wants to know whether a story is newsworthy and whether it's accurate?""Yes," replied Mr O'DriscollThe prosecutor went on: "And one of the ways you can attest to the accuracy of a story is to say our man in a district has a source on the inside?"

Mr O'Driscoll responded: "I'm not sure I would be saying that... mostly he or she [the editor] would be scrutinising them at that stage for newsworthiness."

It's your job to make sure they stand up at the end of the day with official comments."

Challenged on whether he would not place greater reliance on what a reporter would tell him than a black cab driver, Mr O'Driscoll said: "In my experience, the black cab driver gets it right more often."

Mr Goldsmith said the editor would be interested to know there were sources in the police, the army and Broadmoor, telling the defendant: "The obvious question to ask you is: 'Where does it come from, how do we know about it'?"It might seem the most obvious question to you, but that's not how it would happen," Mr O'Driscoll said.

Mr Glasgow challenged the news editor's assertion that he had no idea whether the sources being quoted by his reporters were accurate. He pressed: "The articles are littered with quotes from the inside or source. They talk about a Broadmoor source, a police contact - it gives the impression that the person quoted is a member of staff within Broadmoor or a police officer."

Mr O'Driscoll replied: "No... I think within every newspaper it might say a Broadmoor source, a police source. It's colour. It quite often comes out of a journalist’s pen rather than an official."

Mr O'Driscoll, who left The Sun in 2011 to join the Daily Mail, denies three counts of conspiring to commit misconduct in a public office.

His former boss, news editor Chris Pharo, Mr Pyatt, reporter John Troup, picture editor John Edwards and managing editor Graham Dudman also deny conspiring to commit misconduct in a public office.

The case continues.