Media owner Rupert Murdoch told the media ethics inquiry in London today that he and senior executives were shielded by subordinates from any knowledge of phone hacking at the U.K. newspaper the News of World.

Murdoch, testifying for a second day at the inquiry led by Lord Justice Brian Leveson, said a "clever lawyer" had forbidden journalists with knowledge of phone hacking at the Sunday tabloid from bringing it to the attention of people such as News International chief executive Rebekah Brooks or his son, James Murdoch.

"This person forbade them to go to Mrs. Brooks or James," he said.

Reuters reported that the remark was a thinly veiled reference to the News of the World's former top lawyer, Tom Crone, who has accused James Murdoch of lying.

The 81-year-old media magnate condemned phone hacking and other misdeeds at his papers, but claimed he was unaware of its scope.

"All I can do is apologize," he said.

Murdoch acknowledged that the scandal at the Sunday tabloid last July was a "serious blot" on his reputation and that he didn’t do enough to stop it, but he claimed his company has moved on.

"I failed," Murdoch said at one point. "And I'm sorry about it."

Still, his actions since then have had the right effect, he suggested.

"I've spent hundreds of millions of dollars" cleaning up News Corp. subsidiary News International, Murdoch told the inquiry. "We are now a new company altogether."

On Wednesday, Leveson and inquiry counsel Robert Jay took Murdoch through numerous examples of his relationships with politicians and whether his "commercial interests" were being promoted in them.

'Drinking pal and clever lawyer'

The day before, in testimony by James Murdoch, a cache of emails revealed an apparently cozy relationship between Murdoch companies and an adviser to Culture Secretary Jeremy Hunt. The adviser resigned later in the day.

Thursday's focus was on News of the World and the rampant phone hacking unearthed primarily by the rival Guardian newspaper.

While he pointed to the journalists' "drinking pal and clever lawyer" who helped shield executives from the scale of phone hacking at News of the World, Rupert Murdoch again acknowledged it was wrong. He closed the paper in July and apologized generally for its misdeeds.

"That's not to excuse on our behalf at all," he said Thursday. "I take it extremely seriously that that situation had arisen."

Prime Minister David Cameron set up the inquiry last July to investigate phone hacking at News of the World specifically and media ethics generally.

The relationship between Cameron and Murdoch is getting more complicated.

Cameron is leading a Tory minority government more likely to be pleasing to Murdoch, so there are evidently some rising tensions.

Andy Coulson, a former News of the World editor who resigned over phone hacking, went on to become Cameron's personal spokesman. He left under fire in January 2011, when the phone-hacking allegations were revived.

Queried about commercial interests

Murdoch dismissed Cameron in just three words on Wednesday. Asked if, as reported, he had initially found Cameron to be lightweight, Murdoch replied, "No. Not then."

Toward the end of his appearance, Murdoch was queried by other lawyers about his commercial interests and attitude to organized labour in his newspapers.

His actions, he said, had added mightily to the number of television stations available to British viewers and the number of newspapers available to readers.

"I have contributed to the plurality" of stations and newspapers, he said.

"If I hadn't beaten the old craft unions … there wouldn't be such a good, democratic press" in the U.K., he added.

He rejected a suggestion from a lawyer for the National Union of Journalists that there was a culture of bullying by editors at the News of the World.