Thursday was a jubilant day for Michael Avenatti. According to the lawyer, President Trump's newly claimed ignorance about his nondisclosure agreement (NDA) helps Stormy Daniels, Avenatti's client, make her case. And he's right: The president's claim could potentially be used in court to help invalidate the agreement. If Trump didn't know about the NDA and its accompanying $130,000 "hush money" payment, it would be tough to argue that he had lawfully entered into the agreement.

Trump said that "no," he hadn't known of the NDA payment while speaking to reporters Thursday on Air Force One. When asked why the payment was made, he replied, "You'll have to ask Michael Cohen. Michael is my attorney. You'll have to ask Michael."

That exchange marked the first time that Trump had commented publicly on the NDA. Last month, White House Press Secretary Sarah Huckabee Sanders had suggested that the president was ignorant of Cohen's payment, saying that she wasn't "aware of" any knowledge the president had about it.

Avenatti took to Twitter to celebrate the president's comments on Thursday. "Good (actually GREAT) things come to those who wait!!!" he wrote. "The strength of our case just went up exponentially. You can't have an agreement when one party claims to know nothing about it."

He rejoiced in his and Daniels' good fortune during an MSNBC interview on Thursday evening. "It's a very, very Merry Christmas this evening here over in our camp," Avenatti said.

If Trump truly didn't know about the NDA, that could enable a court to declare the agreement invalid. Avenatti argued as much in a recent motion to depose both Trump and Cohen. He cited California Civil Code (the document was submitted in federal court in the Sunshine State), which stipulates that "Consent is not mutual, unless the parties all agree upon the same thing in the same sense." Trump couldn't have been a consenting party to the NDA if he didn't agree to it, the argument goes.

But here's the thing: It's possible that Trump could have been lying to reporters about his ignorance. That may even be the more likely scenario — would Cohen really have entered into an NDA on behalf of his client without telling him? The Wall Street Journal reported last month that Cohen was complaining to friends about not getting reimbursed by Trump for the $130,000 payment. If the president intended to pay Cohen back, he must have known about the NDA.

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Avenatti seems to think that Trump was lying on Air Force One. "We very much look forward to testing the truthfulness of Mr. Trump's feigned lack of knowledge concerning the $130k payment as stated on Air Force One," he tweeted on Thursday. "As history teaches us, it is one thing to deceive the press and quite another to do so under oath."

If Trump was lying, what does that mean for the Stormy Daniels case? If he were deposed and continued to lie, that would be committing perjury. On the other hand, if he admitted to knowing about the NDA under oath, he would also be acknowledging that the alleged affair with Daniels happened. That outcome could also help Daniels' new defamation case, in which she argues that Cohen tried to discredit her as a liar.

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Basically, things aren't looking great for Trump. At this point, there seem to be only a couple of ways out for him. If the case moves to arbitration like he wants it to, it will be settled in private, so the public won't know the case's outcome or what Trump says in the proceedings. There's also a scenario in which Cohen publicly wins the case without needing to prove that Trump knew about the NDA. But that's unlikely, since the agreement is full of provisions to which David Dennison, Trump's pseudonym, was supposed to agree.

Avenatti seems to be right about this. It's April for the rest of us, but a very delightful Christmas where he and Daniels are sitting.