Transcript for Bernie Sanders: Donald Trump is a 'Pathological Liar'
Does secretary Clinton deserve an apology tonight? Yes, I apologize. Secretary Clinton, do you accept? Not only do I apologize to secretary Clinton, and I hope we can work together on an independent investigation from day one, I want to apologize to my supporters. This is not the type of campaign that we have and if I find anybody else involved in this, they will also be fired. Opening moments last night with senator Bernie sanders, he joins us live here in new Hampshire this morning. I want to get to that in a second, but first, you just heard Donald Trump called you out, saying you lied. I tell you, he's rather extraordinary. I think, and I say this straightforwardly, I think you have a pathological liar right there. Most of what he says is a distortion of facts. He's saying over and over again that he saw thousands of people in New Jersey celebrating 9/11 the destruction of the twin towers, either that's true or or not true. From what I understand, there's have been a lot of research, they archive what goes on TV. You're a TV guy, everything we are saying is going to be archived. Nobody has seen a tape of thousands of people celebrating the destruction of the twin towers in New Jersey. It doesn't exist, and he keeps claiming that. That's called pathologically lying. Yes, a few moments ago, he accused me of lying. What I said last night he suggested that Mexicans who are coming to this country are criminals and rapists, that's exactly what he said. What somebody like a Donald Trump is doing is playing on the fears and anxieties of the American people and people are afraid. They're afraid of terrorism, rightfully so. They're anxious about an economy in which the middle class is disappearing. People are worried about the future for their kids. These are legitimate fears. So, instead of having a rational discussion about how we rebuild Wall Street, what trump is, it's all the muslims' fault. How do you explain why that's doing so well right now? Because it's an easy solution. How do we rebuild the middle class? Well, you're going to have to stand up to corporate America. You're going to have to stand up to Wall Street. By rebuilding our infrastructure. You'll have to provide health care to all people. What trump says, this is what demagogues have done. Are you nervous, are you scared, frightened for terrorism. It's the muslims out there are terrorists. We have stop them coming into this country. It's the Mexicans, it's the immigrants who are coming in. They're all rapists and criminals. Meanwhile, trump is saying the middle wage in America, $7.25, he said it's good that we have a low minimum wage. This guy trump is saying, we need to give billions of dollars of tax breaks to the very richest people in this country. How do you defeat that? By going out to the working people of this country and making it clear, if we're going to create an economy that works for our kids and for working families, we have to do it together. And understand the real causes. The greed of corporate America. The greed of Wall Street. Not some poor Mexican who's in this country trying to live on $7 a country. I want to ask you about that moment about the apology on the bat that breach by one of your staffers. You suspended two more staffers. Is that it, is the discipline finished? We're still trying to figure out. One thing that bothered me, as I understand it, the dnc has been giving out information to the media, giving out before the Clinton campaign before we're even getting it. This is not the first breach caused by a dnc vendor, all right, it's at least the second. And what I want to see is an independent investigation going on in this campaign. You sals said last night that you're not convinced that the Clinton team didn't take a look at the data, do you have evidence of that? No. The first time it happened and when my staff saw it, they said, wait, this is really bad. They went to the dnc and went to the vendor. Second time, one or more of my staff acted inappropriately. I want an independent investigation. I'm saying it's absolutely a possibility. Your campaign has been pretty tough on the dnc. Your campaigning manager has said that they're actively trying to undermine our campaign, even sabotage, is that what you believe? Look, a staff member or more on my team acted inappropriately. We're going to deal with that. But, to shut off access to my campaign's information, what word would you use? Sabotage? We -- those are the people we're trying to contact. We for two days couldn't access that information. That's total overreaction. What should have been done, there should have been a meeting between the teams, quietly, we got a problem, how are we going to address this problem? Not leaking stuff to "The Washington post." And certainly not separating us and preventing us from getting the information we need to run a campaign. Big difference between you and secretary Clinton last night on the issue of taxes, she made a pledge of not raising taxes. You talked about the tax to pay for the family leave bill. You said it was about $1.61 for a family each week. That's not it. How are you going to pay for the rest of it? All right, fair question. We're going to provide free tuition to public colleges and universities. By imposing a tax on Wall Street speculation. That tax will pay completely for public tuition at public colleges and universities and substantially lower interest rates on student debt. We're going to rebuild our crumbling infrastructure. Through a trillion-dollar investment to create jobs by doing away with the loopholes that currently exist by which corporations can stash their money in cayman islands. We're going to raise social security benefits, expand benefits by lifting the cap on taxable income going into social security. People making $250,000 a year or more will pay the same percentage of their income. Still have to pay health care? No, that will expand social security benefits for people who are trying to live on $12,000 or $13,000 a year. But in terms of this -- the United States is the only major country on the Earth doesn't have paid family and medical leave act. It's a disgrace. Every other country on Earth has paid family and medical leave. I'm supporting legislation introduced in the house and the senate, which has all Progressive democrats onboard, it will cost a $1.61 a week. Is that it? No other tax increases on the middle class? That's it. Final question on the regime change, the big difference you said last night between you and secretary Clinton, but where is the difference going forward? I don't agree with the no-fly zone in Syria, I think it can get us sucked into some serious problems in the area. I think absolutely there has to be a strong international coalition -- and this is what I believe -- king Abdullah of Jordan has made this point, the war that's going on is for the soul of Islam, what he believes and I believe -- Muslim troops themselves, Muslim countries have to come together on the ground to take on Isis. What I also believe is that wealthy countries, like Qatar, the wealthiest country on Earth, spending 20$2020 billion on the world cup, they're hosting the world cup in 2022, they'll have to help us destroy Isis.
This transcript has been automatically generated and may not be 100% accurate.