Image caption Abramoff, shown here after his 2006 guilty plea, owes millions in restitution

Jack Abramoff, a former lobbyist imprisoned for his role in a wide-ranging Washington corruption scandal, has appeared as a pundit on CNN. Why have US television networks turned into comeback springboards for disgraced public figures?

On Thursday, Abramoff joined presenter Soledad O'Brien, New Yorker writer Ryan Lizza and others to analyse the recent US Supreme Court decision ratifying President Barack Obama's healthcare reform law.

Introducing Abramoff, O'Brien acknowledged he had spent more than three years in federal prison - then plugged his new book.

She questioned him about the impact of the healthcare decision on the lobbying profession and how lobbyists would seek to influence Congress on the matter.

"Always nice to have you," she concluded. "We appreciate it. Thank you."

US television networks and media outlets in recent years have been increasingly willing to help rehabilitate disgraced politicians and public figures by offering them air time.

Political crooks, a stock market hype-man, an insider-trading cheat who lied to federal investigators and others have all turned their fortunes around in part because the American television networks long ago relinquished their role as a moral arbiters, analysts say.

The journalistic mission became secondary to using notorious names to attract audiences.

"Is there a financial news channel that wouldn't take an appearance from Bernie Madoff?" asks Todd Gitlin, a sociologist and professor of journalism at Columbia University, referring to the notorious architect of a multi-billion dollar pyramid scheme, now imprisoned for the rest of his life.

"I don't see what would stop them. Why should they hesitate to promote a crook as somebody who has some knowledge gleaned in the course of crookery?"

Abramoff's transgressions are in a far more sinister league than most.

Image caption G Gordon Liddy was jailed over the Watergate scandal, but that did not keep him off Fox News

He lavished gifts and travel on Bush administration officials and Congressional staff, while ripping off Indian tribes who had hired him to further their gambling interests in Washington.

Abramoff came to symbolise an out-of-control political culture of influence peddling among corporate interests, lobbyists, politicians and their aides.

Several top Republican Congressional aides, Bush White House and administration officials, lobbyists and a Republican congressman were convicted and imprisoned.

Public disgust with the Republican Congress over the scandal is credited with helping pave the way for the Democratic takeover of the House and Senate in 2006.

Abramoff ultimately pleaded guilty to federal corruption charges. He also lied to his clients and evaded taxes.

He was released from prison in December 2010. This year he published a memoir, Capitol Punishment, and began touring the television networks to flog it.

The redemption will be televised Eliot Spitzer , who in 2009 resigned as governor of New York upon admitting he had visited a prostitute, has presented television shows on CNN and Current TV

who in 2009 resigned as governor of New York upon admitting he had visited a prostitute, has presented television shows on CNN and Current TV Lifestyle guru Martha Stewart returned to television soon after serving five months in federal prison for lying to investigators in an insider stock-trading scandal

returned to television soon after serving five months in federal prison for lying to investigators in an insider stock-trading scandal Henry Blodget , a disgraced former Wall Street analyst barred from the securities business and fined $2m after hyping tech stocks during the 1990s bubble, regularly contributes analysis to CNN business coverage

, a disgraced former Wall Street analyst barred from the securities business and fined $2m after hyping tech stocks during the 1990s bubble, regularly contributes analysis to CNN business coverage Watergate villain G Gordon Liddy has appeared frequently as a guest on Fox News Channel chat shows, andn has long been a television pitchman for a gold investment broker that advertises on cable news channels

Washington is packed with lobbyists, many of whom actually specialise in healthcare and the vast majority of whom, to say the least, have not been convicted in historic corruption scandals.

CNN's decision to book Abramoff on a morning news panel illustrates the contempt its producers have for its audience, says Ron Powers, a Pulitzer Prize-winning television critic.

"It's a way of saying to the viewer: 'We put this guy on the air not because he has any particular expertise, but because we have a strong suspicion you don't read much, and here is a name that you can maybe titter over,'" he says.

People know Abramoff's name, while they are unlikely to know a better informed, less notorious healthcare lobbyist, analysts say.

"The wonder of seeing Jack Abramoff discoursing on healthcare trumps any moral consideration not only on his credentials but also that he was once an enemy of society," Powers says.

Gitlin of Columbia recalls seeing firebrand rightwing radio figure Rush Limbaugh interviewed by Tim Russert on prominent Sunday morning chat show Meet the Press about a confrontation between Bill Clinton and Saddam Hussein in the 1990s.

"I was flabbergasted to see him there," Gitlin says. He called Russert and asked why the show had booked Limbaugh.

"The answer was not he knows something about Iraq," Gitlin says. "He said to me, 'he speaks to 20 million people.' That was a marker of what is considered valuable about a person on exhibit on a major news show."

Image caption Stewart quickly rejoined her media and lifestyle empire after being sprung from federal prison

The decline of public moral standards that can facilitate a convicted criminal like Abramoff's redemption on television news began with the moral relativism of the 1960s, says sociologist John Macionis of Kenyon College in Ohio.

"We live in a world where it's much harder to define good guys and bad guys," he says.

In the 1960s, the loud public rejection of the War in Vietnam, the civil rights movement, the birth of the women's liberation movement, and other social phenomena led to a rejection of conventional value hierarchies, Macionis says.

The subsequent pervasion of moral relativism created an atmosphere that made people uncomfortable passing judgement on crooks, he says.

"The so-called conventional good guys, we started to think they may be really bad guys," Macionis says. "And the bad guys: they could be seen as just saying 'hell no, we won't take it any more. [Being a bad guy] doesn't seem to disqualify anyone anymore."