Transcript for Trump campaign launches legal action against ex-aide

First we begin with that escalating battle between president trump and his former aide, omarosa manigault-newman. The trump campaign this morning is now taking legal action against omarosa, accusing her of violating a nondisclosure agreement. This morning, a new secret recording now raising questions about the president and whether or not he used a racial slur during his time on the apprentice. Can the white house guarantee the American people will never hear it? Our chief white house correspondent Jonathan Karl leading us off this morning with the very latest. Good morning, Jon. Reporter: Good morning, David. As his campaign lawyers try to silence omarosa, the president is in counter-attack mode. Trump campaign lawyers are trying to force omarosa to keep quiet, accusing her of violating a nondisclosure agreement she signed during the 2016 campaign. She isn't backing down. What is he trying to hide? What is he afraid of? If he hadn't said anything that was derogatory or demeaning to African-Americans and women, why would he go to this extent to try to shut me down. Reporter: The feud has become deeply personal, the president taking to Twitter to call her a crazed crying low life, adding, good work by general Kelly for quickly firing that dog. Is this any way for a president to talk about any American, let alone somebody that he hired and made the highest ranking African-American woman that served in his white house? I think the president is certainly voicing his frustration with the fact that this person has shown a complete lack of integrity. Why did he hire her? I mean, why did he hire somebody he's describing as a dog? The president wanted to give her a chance. Reporter: Among omarosa's many explosive charges, that the president had been caught on tape using the "N" word back when he was doing the apprentice. On Twitter, the president insisted there are no tapes of the apprentice where I used such a terrible and disgusting word, as attributed by wacky and deranged omarosa. I don't have that word in my vocabulary and never have. The white house press secretary was asked if she could guarantee there are no tapes of the president using that racial slur. I can't guarantee anything, but I can tell you that the president addressed this question directly. I can tell you that I've never heard it. Reporter: And yet another recording released by omarosa, this one to CBS news, omarosa says trump campaign spokesperson Katrina Pearson and campaign aide Lynn Patton are heard talking during the 2016 campaign about whether trump may have used that slur on an alleged tape. I'm trying to find out at least what context it was used in to help us maybe try to figure out a way to spin it. I said, well, sir, can you think of any time that this might have happened and he said no. Well that's not true, so -- He goes, how do you think I should handle it? And I told him exactly what you just said, omarosa, which is, well, it depends on what scenario you're talking about. He said, why don't you go ahead and put it to bed. He said it. No, he said it. He's embarrassed. Reporter: Those aides are now saying they were just responding to rumors and that they themselves never heard trump use derogatory language on any alleged tape. Sarah Sanders is also firmly denying omarosa's description of the president as a racist, saying of the white house staff, quote, if at any point we felt the president was who some of his critics claim him to be, we certainly wouldn't be here. David. All right, Jon Karl at the white house this morning, thanks to you. Let's bring in our chief legal analyst Dan Abrams. What do you think of this notion of them trying to enforce this nda now to try to get omarosa to stop talking? Nda's are notoriously tough to enforce. Add to that the fact that you're talking about trying to get a former government employee to not talk about the president of the United States and you now have additional first amendment concerns. So, the president would say and their team would say this is the campaign suing, it's not the president. That doesn't change the reality that you're talking about trying to get a former government employee not to be able to talk. This is going to be a very difficult nondisclosure to enforce. Because she went from campaign worker to a key government employee in the west wing. And because nda begin from the evaluation of being very tough to enforce. Let me ask you, Dan, can she say anything she wants? Because in the last 24 hours she's also saying that president trump had prior knowledge of those hacked nda e-mails before wikileaks released them. That's a huge accusation with no proof. Right. If what she's saying isn't true, rather than trying to enforce her nda, they should be suing her for defamation and libel. That to me would be a stronger claim if everything she's saying is false. But in the context of the bigger investigation, the Robert Mueller investigation, you can count on the fact that they are going to take anything and everything she says with an enormous grain of salt. There is no way they're going to take something she says as gospel. There's going to have to be major corroborating evidence for anything she says to be used significantly. She offered no proof in the book. Otherwise we would be talking about something else this morning. That's right. Dan, thanks as always.

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