Media mogul Murdoch and his son James were called upon to answer questions about the now notorious phone-hacking scandal, which prompted them to close the News of the World earlier this month (Jul11).
Murdoch shut down the 168-year-old tabloid amid allegations a private investigator working for the publication had illegally accessed voice mail messages belonging to royals, celebrities, and the families of crime victims.
At the hearing, MP Louise Mensch, while questioning Rupert Murdoch, claimed Morgan - who was once editor of the News of the World - had "boasted" about hacking phones to get stories in his 2005 book The Insider: The Private Diaries of a Scandalous Decade.
Morgan was left furious by Mensch's accusations, taking to his Twitter.com page to refute her claims, before later confronting the politician in a phone call during an interview on CNN.
When he pressed her to admit she was wrong, she refused to comment, insisting she couldn't repeat what she had said during the hearing because she was no longer protected by the legal immunity afforded inside British Parliament.
He then vented his anger on Twitter, writing, "That MP just claimed I boasted in my book of using phone-hacking for a scoop. Complete nonsense. Just read the book. I've never hacked a phone, told anyone to hack a phone, or published any stories based on the hacking of a phone. I wrote in my book that someone warned me phones could be hacked, so I changed my pin number. That's it.
"Ms Mensch said she couldn't repeat allegations because she wouldn't have parliamentary privilege to protect her. Laughable and cowardly. You lied today LouiseMensch - and you don't have the guts to admit you lied. Read the book and apologise."