The Connecticut Democrat regarded as "the conscience of the Senate" fielded a few questions with ethical edges on CBS News' Face The Nation on the eve of this week's Democratic National Convention in Los Angeles.
Now that he's on the Democratic ticket, Lieberman was asked whether he'd tolerate the 1996 campaign finance practices that have plagued President Clinton and Vice President Gore ever since.
"I don't think I'd have to argue with him," said the senator of Gore, the Democratic presidential candidate. "I'm sure that none of this will happen in a Gore White House."
I've talked to Al Gore about this and he said that there was some mistakes made in '96, the whole system went out of control in both parties but, you know, he's already learned a lesson," said Lieberman of the White House coffees and Lincoln Bedroom sleepovers for major campaign contributors.
"There's nothing approaching those coffees going on in the Gore campaign, and I can promise you there won't be in a Gore-Lieberman administration," he added.
The senator pointed out the Democratic team was the only ticket that backs the McCain-Feingold bill. Gore has promised that the campaign finance reform legislation would be the first bill he would send to Congress if elected president.
And Lieberman was asked about the estimated $20 million retirement deal for his counterpart, GOP vice presidential nominee Dick Cheney, from the oil services firm Halliburton.
The senator replied the deal, while perfectly legal, might prompt voters to ask pointed questions about the Bush-Cheney team, such as "How could this ticket be against increasing the minimum wage for instance for the lowest paid workers in America? Why are they proposing a privatization system for Social Security that will jeopardize the retirement of average people while they're enjoying this benefit?"
Bush has said he won't ask Cheney to recuse himself on issues that might affect the oil industry. Lieberman added both GOP candidates ought to release their tax returns, just as he and Gore have done.
"When you're in public life, you've got to accept as part of that opportunity to serve a responsibility to disclose just about everything about yourself," he said.
Also on Face The Nation, Gore campaign chief William Daley downplayed concerns that President Clinton was dominating this week's convention in L.A. to Gore's political expense in November.
"The president has every right and an obligation to come out here and say thank you to Democrats who have stood with him in good times and in difficult times," said Daley. "He is not only extremely well respected, but liked by the Democrats. And he's out here enjoying, as he should, his final convention as president."
What about Mr. Clinton's remarks on the Monica Lewinsky scandl last week, when the president urged people not to blame Gore for his personal behavior?
"The president did that in a setting that was about leadership. And it was a personal statement of his," Daley said. "It was not something that was a political spin to it. And I think that issue ... the American people have dealt with almost two years ago now."
And what about First Lady Hillary Rodham Clinton? Last week, the U.S. Senate candidate in New York said she had more of a role in shaping and lobbying for White House policy than she revealed after the failure of her health care reform plan.
"There is no question she has been a major force in policy development and implementation over the last eight years," said Daley of Mrs. Clinton. "Maybe not with the visibility that some people would have expected, but she very much has strong opinions, and understands the president's direction."
Jokingly, Daley added, "Maybe there is great joy in the fact that there is one secret that's been kept in this administration."