Lord Patten, the chairman of the BBC Trust, has argued against statutory regulation of newspapers in a lecture at the Society of Editors' annual conference.
In a speech entitled Ethics and Journalism after the News of the World, he said proper reform can only be achieved by journalists.
Lord Patten, the last governor of Hong Kong, said: "Statutory regulation of the press would in my view be more than wrong-headed, it would pose a real danger to the public discourse that underpins our democracy. So the responsibility to ensure high standards of professionalism rests with journalists, their editors and their proprietors."
Lord Patten said he may have to go before the Leveson Inquiry - into the culture, practices and ethics of the press.
He said: "If so, I hope I can make a convincing case that the sort of regulation that covers us is appropriate for broadcasters but would not work for newspapers.
"There is a kind of symbiosis between the BBC and the press. We do different but complementary things. The BBC depends on the press for some of its news agenda and it gives some stories back to the press to pursue further.
"The style of the tabloids is not something we could or should try to match. But nor should we be snobbish or squeamish about it."
The former cabinet minister acknowledged the "alleged hacking and police pay-offs were indefensible," but applauded tabloid papers' "vitality" which contributed to the public good.
"I have no wish to turn our tabloids into trimmed down versions of The Church Times," he said.
"Their vigour is an important part of the liveliness of our democracy. Free speech, and therefore that vitality, would truly be damaged if a single group of people, beholden to and perhaps even appointed by politicians, were to have the power to decide what should or should not be published."