Ian Burrell edits the Media Weekly pages of The Independent.
The controversy relates to the ongoing News of the World phone-hacking affair, and the PCC's claim in a report a week ago that The Guardian had produced "no evidence" that the practice was ongoing at the tabloid, despite prominent stories in July, which led to a House of Commons committee calling an inquiry.
Within a day of making her inaugural speech as chairman of the Press Complaints Commission, Baroness Buscombe is facing a call for her to resign.
At the end of her first speech, given to the Society of Editors conference last night, Baroness Buscombe told the audience that MPs on the committee may have been misled by evidence that alleged that 6,000 people had been victims of phone-hacking by the News of the World. She said that Scotland Yard lawyers, acting on behalf of a police detective said to have given this figure, had told the PCC he had been misquoted. Only a "handful" of people had been victims, the Yard had said.
But now the Manchester-based lawyer who gave the select committee the 6,000 figure, Mark Lewis, has hit back, standing by his account and calling on Baroness Buscombe to step down. "I regret that your failure to act properly has compromised any veneer of impartiality that you sought to create," he said in a letter to the PCC, copied to the select committee.
Mr Lewis said that his conversation with the police detective had taken place in the presence of two witnesses.
The Culture select committee, which has taken evidence from numerous witnesses, including the former News of the World editor and now Conservative communications director Andy Coulson, is due to publish its own report shortly.