The editor on the Mail on Sunday today conceded that the paper used private investigator Steve Whittamore after he had been charged with illegally trading information.

Peter Wright, who has edited the paper since 1979, told the Leveson Inquiry that Whittamore was used in a “small number of cases” after he was charged in February 2004.

In the same month, Wright said he instructed staff not to use Whittamore “unless there was an extremely good reason and all other means had been exhausted”.

Wright said the Mail’s use of Whittamore “virtually stopped altogether” in September 2004. Whittamore was given a conditional discharge in 2005.

During a lengthy exchange with Robert Jay QC and Lord Justice Leveson, Wright said he discovered in August 2011 that Whittamore provided information illicitly to some reporters. “I was uncomfortable that it appeared he might be using methods of which we would not approve, without the knowledge of those who were commissioning him,” he said.

Operation Motorman, carried out in 2003, investigated the use of a private investigators by the media to obtain personal information. In the 2006 report published by the Information Commissioner’s Office disclosing the 22 newspapers that had regularly used Whittamore to access illegally-obtained information, the Daily Mail topped the list with 952 transactions. The Mail on Sunday came fourth, with 266 transactions.

Wright said Whittamore had been used for a story published in February 2003 to establish the ownership of a scooter used by union leader Bob Crow.

He said: “Whittamore didn’t supply stories. He was used primarily to find names and addresses of people we needed to speak to in the course of researching stories.” He added that Whittamore was paid a total of £20,000 to trace information.

He said that Associated Newspaper’s request to see the ICO’s report was turned down, although the company accepted its findings.

Wright also said he did not believe the paper’s staff had used phone hacking to obtain stories.

“I have absolutely no evidence that phone hacking ever did occur,” he said. “I would hope that if phone hacking had been going on that it would have been brought to my attention.”

Follow Index on Censorship’s coverage of the Leveson Inquiry on Twitter – @IndexLeveson