LONDON - News Corp Chief Executive Rupert Murdoch and his son James face questions from parliament on Tuesday in a phone-hacking and corruption scandal that has rocked Britain's establishment right up to Prime Minister David Cameron. Britain's Channel 4 News is webcasting the hearings.With a second British police chief quitting on Monday over the scandal, Cameron cut short a trade trip to Africa and was due to return in time for an emergency debate on Wednesday in parliament, which is delaying its summer recess.Speaking in Lagos, Nigeria, shortly before flying home, Cameron said he was committed, through a new public inquiry and a police investigation, to addressing three key problems: "The wrongdoing in parts of the media and the potential that there is corruption in the police and ... the third ... which is the relationship between politicians and the media."But he also signalled a desire to push the agenda away from a scandal that has dominated every debate for two full weeks: "The British public want something else too," Cameron said.RELATED:UK police arrest Murdoch ally Rebekah Brooks UK police under scrutiny, Murdoch tries to damp fire Murdoch apologizes over scandal, two lieutenants out"They don't want us to lose our focus on an economy that provides good jobs, on an immigration system that works for Britain, a welfare system that is fair for our people."The Murdochs' appearance before parliament's media committee was expected to attract a television audience of millions keen to follow the latest twist in a saga that has shaken faith in the police, press and political leaders. "It seems as if there will be standing-room only. That's not surprising as it's the first time Rupert Murdoch has been before a select committee in his 40 years of building up a media empire," said Paul Farrelly, an opposition Labour committee member.The 80-year-old, Australian-born Rupert Murdoch arrived more than two hours before he was due to appear. Smiling from the back seat of his car as he drove in, he sat beside a copy of the Wall Street Journal, the U.S. paper he bought in 2007."I want to feel the atmosphere in the room and actually witness history unfold," said Max Beckham, 21, from London as he lined up for one of the few public seats on offer. "This hearing could signal the end of Rupert Murdoch's reign."Another eager witness in the public gallery, Canadian tourist Andy Thomson, 40, called it "the best show in town.US-based Murdoch's British arm, News International, had long maintained that the practice of intercepting mobile phone voicemails to get stories was the work of a sole "rogue reporter" on the News of the World newspaper.That defense crumbled in the face of a steady drip-feed of claims by celebrities that they were targeted.The floodgates opened two weeks ago when a lawyer for the family of a murdered teenage schoolgirl said the paper had hacked her phone when she was missing, deleting messages and raising false hopes she could be still alive. The ensuing outrage prompted News Corp to close the 168-year-old News of the World and drop a $12 billion plan to take full control of pay TV operator BSkyB , and saw the arrest of former News International Chief Executive Rebekah Brooks, a Murdoch protégée who once edited the newspaper.Cameron has faced questions over his judgment in appointing former News of the World editor Andy Coulson as his communications chief, while London police chief Paul Stephenson and anti-terrorism head John Yates stepped down over links to Coulson's former deputy, appointed as an adviser to the police.