At one point, Jay quizzed Murdoch about a gleeful comment in which he took credit for smearing his left-wing opponents.
"If I said that, I'm afraid it was the influence of alcohol," Murdoch replied.
Throughout the hearing, Murdoch attacked the idea that he traded on his political influence, calling it a "complete myth. One I want to put to bed once and for all."
So determined was he that at one point Murdoch seemed to claim he was totally blind to business considerations when deciding which politicians to back.
"You're completely oblivious to the commercial benefits to your company of a particular party winning an election. Is that really the position?" asked a skeptical-sounding Jay.
"Yes," Murdoch said. "Absolutely."
Murdoch's testimony resumes on Thursday.
Inquiry website: http://www.levesoninquiry.org.uk
Murdoch's witness statement: http://bit.ly/IDp5rc
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