Transcript for President Trump's legal team set to continue his defense
Next tonight, the impeachment showdown, as president trump's legal team will ramp up the defense on the senate floor tomorrow. Let's get right to David Wright, at the white house tonight. Reporter: One major line of defense from president trump's lawyers is the claim that the two articles of impeachment approved by the house are constitutionally invalid. The conduct has to be criminal in nature. It can't be abuse of power. It can't be obstruction of congress. Reporter: Former Harvard law professor Alan Dershowitz insists that should be game over. If my argument succeeds, there's no need for witnesses. Indeed, there's no need for even arguments, any further arguments. Reporter: But Dershowitz argued the opposite during bill Clinton's impeachment. It certainly doesn't have to be a crime. If you have somebody who completely corrupts the office of president and who abuses trust and who poses great danger to our liberty, you don't need a technical crime. Well, I did say that then, and then I've done all the extensive research. Reporter: Today, Fox News anchor Chris Wallace called him out on his about-face. You're too good a lawyer not to have studied that back in 1998. I've been immersing myself in dusty old books and I've concluded that, no, it has to be a crime. His team of lawyers can try to distort and try to deflect but, quite frankly, the best witness that we have in this case is the president of the United States. Reporter: Today president trump called out the house's lead impeachment manager, congressman Adam Schiff, calling him, quote, "A corrupt politician, and probably a very sick man. He has not paid the price, yet, for what he has done to our country." This is a wrathful and vindictive president. I don't think there's any doubt Do you take that as a threat? I think it's intended to be. David, tomorrow, the president's lawyers continue their defense. But the Democrats don't appear to have the votes to force the issue on witnesses. Reporter: That's right, they need four Republicans to break rank. So far, only Mitt Romney has made it clear he's learn leaning in that direction. Three others are being a bit more coy, but they haven't ruled
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