British Prime Minister David Cameron defended a former aide embroiled in a major phone hacking and bribery scandal but told Parliament on Wednesday that in “20/20 hindsight” he would not have hired the tabloid editor as his communications chief.

In a special session before the House of Commons, Cameron rebuffed catcalls from the opposition to defend Andy Coulson, who is one of nearly a dozen people arrested in an investigation of phone hacking and corruption at the now-shuttered News of the World.

“I have an old-fashioned view about innocent until proven guilty, but if it turns out that I’ve been lied to, that would be a moment for a profound apology,” the prime minister said. “In that event, I can tell you that I will not fall short.”

Coulson was editor of the News of the World — a tabloid known for sensational stories featuring crime, celebrities and politicians — until 2007 when he resigned after one of the paper’s reporters was convicted of phone hacking. He was later hired by then-opposition leader Cameron.

But even as Cameron spoke on behalf of Coulson, the prime minister apologized for “the furor” his hire has caused.

“With 20/20 hindsight and all that has followed, I would not have offered him the job and I expect that he [Coulson] wouldn’t have taken it,” Cameron told Parliament. “But you don’t make decisions in hindsight; you make them in the present. You live and you learn. And believe you me, I have learned.”

The tabloid scandal caught fire two weeks ago amid revelations that the Rupert Murdoch-owned News of the World reporters intercepted the cell phone voice mail of a 13-year-old murder victim, possibly destroying evidence in the process. The scandal felled the tabloid, which was shut down by Murdoch’s News Corp. earlier this month after 169 years in print.

So far, only a fraction of some 3,870 people whose names and telephone numbers were found in News of the World files have been contacted by police. It is still unknown how many of those names were actually victims of hacking.

The allegations have also sparked renewed questions about whether News of the World paid police for inside information that could lead to salacious scoops. The two top officers of London’s Scotland Yard, Commissioner Sir Paul Stephenson and John Yates, have resigned amid allegations that their department enjoyed a cozy relationship with the tabloid.

In Parliament on Wednesday, Cameron defended the way his staff has dealt with the police over the allegations.

The prime minister’s office “has now published the full email exchange between my chief of staff and [Assistant Commissioner] John Yates and it shows my staff behaved entirely properly,” Cameron said.

The special session of Parliament where Cameron was on the hot seat followed Tuesday’s grilling of News Corp. executives Murdoch and his son James as well as the former head of the company’s British newspapers, Rebekah Brooks.

A hearing of the Culture, Media and Sports committee questioned a haggard-looking Rupert Murdoch who apologized for the hurt caused to victims of the hacking and for the “broken trust with our readers” but refused to acknowledge any personal responsibility.

The scandal has swept over Murdoch’s News Corp. like a black squall, not only prompting the closure of the lucrative News of the World, but forcing Brooks, a protégé of Rupert Murdoch, to resign. It has also had repercussions on Murdoch’s flagship U.S. newspaper, The Wall Street Journal, forcing the resignation of the paper’s publisher Les Hinton, who was head of News Corp’s British newspapers at the time of the alleged hacking. News Corp. also owns U.S.-based Fox Broadcasting.

In nearly three hours of questions Tuesday — most of which were fielded by News Corp. heir-apparent James Murdoch — the elder Murdoch was unflappable, even after a protester rushed to throw a shaving cream pie at him during the hearing.

A News Corp. attorney partially blocked the attack, and Murdoch’s 42-year-old wife, Wendi Deng, slapped the protester. After the man was arrested, the billionaire simply shed his splattered suit jacket and continued answering questions.

With reporting from Larry Miller in London. Material from The Associated Press was used in this story.

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