Transcript for Will Trump declare a national emergency?

president and what he said today when asked, will he declare an emergency to get his border wall built. The president with border patrol officers in Texas, calling it a crisis. It's now day 20 of the government shutdown. Tonight, house peopler Nancy Pelosi saying the president likes this, saying it's because it's a distraction from what else is happening in Washington. This evening, 800,000 American workers will not get paid, and is the president about to bypass congress to get the wall built? Matt Gutman with what the president said. He's in mission, Texas, tonight. Reporter: Tonight, president trump traveling far from Washington and those stalled shutdown talks, trying to drum up support for his wall, by warning of a national security crisis at the border. If you don't have it, it's going to be nothing but hard work and grueling problems. And by the way, and death. And death. A lot of death. Reporter: But we got a different story from the local mayor, Jim darling. One of the things the president mentioned is that there is a security crisis here. What was the murder rate in McAllen, Texas, in 2018? Zero. Reporter: Zero murders? We're the safest city in the state of Texas. Reporter: The mayor doesn't want a wall here. There's places a barricade makes sense. Reporter: But not necessarily right here. Not my city, no. Reporter: But the president is dug in. Even before taking off, he was sounding ready to declare a national emergency so he can go around congress and use the military to build his wall. I haven't done it yet. I may do it. If this doesn't work out, probably I will do it, I would almost say definitely. Reporter: House speaker Nancy Pelosi pointing out even many Republicans dislike that idea. I think he's going to have to answer to his own party on usurping that much power. I don't think he really wants a solution. I think he loves the distraction that this is from his other problems, and that's most unfortunate. It's a luxury our country can't afford under any circumstance. Reporter: The president long promised American taxpayers would not have to pay for the wall. Who's going to pay for the wall? Mexico! Reporter: His campaign website even spelled out a plan to pressure Mexico to quote, make a one-time payment of $5 to $10 billion. Today, a different story. When I said Mexico will pay for the wall in front of thousands and thousands of people, obviously, they are not going to write a check, but they are paying for the wall indirectly. Reporter: That is not true, either. The president is demanding $5.7 billion from congress for the wall, and says he won't reopen the government until he gets it. Reporters today asking if the buck stops with him. The buck stops with everybody. They could solve this problem in literally 15 minutes. All right, Matt Gutman with us live tonight from Texas. And Matt, we heard president trump say there that he would, quote, probably almost definitely declare a national emergency to allow the military to build his wall. And tonight, you're learning that the head of the army corps of engineers was actually on air force one with the president? R: That's right, David. He came with the president and stayed with him for much of his time here at the border. Now, we've just learned that the white house has directed the army corps of engineers to examine its emergency supplemental budget to see if there's enough money in there for the military to build that wall without additional government funding. David? Matt Gutman in mission, Texas, leading us off. Matt, thank you.

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