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From the Oval Office, President Trump tonight is expected to talk about immigration and the border wall he promised to build when he was campaigning. The White House says Trump is still considering whether or not to declare a national emergency that would let him go around Congress and have the military build the wall. NPR White House correspondent Tamara Keith has this look at whether Trump can do that.
TAMARA KEITH, BYLINE: The short answer is yes he can, but should he? Would it face a legal challenge or cause a government crisis? Those questions have more complicated answers. It's something administration lawyers are vetting, and President Trump said this past weekend that he's considering it.
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PRESIDENT DONALD TRUMP: We have a crisis at the border of drugs, of human beings being trafficked all over the world. They're coming through. And we have an absolute crisis - and of the criminals and gang members coming through. It is national security. It's a national emergency.
KEITH: The Trump administration frequently uses misleading statistics to back up these claims. Illegal border crossings are significantly lower than historical levels but have bumped up recently. And many of those arriving are in families and unaccompanied children seeking asylum. But here's the thing - it doesn't matter whether Congress or the American public see it as rising to the level of a national emergency. Elizabeth Goitein is at the Brennan Center for Justice.
ELIZABETH GOITEIN: The way it works is he declares the emergency. There are basically no limits on that. He just issues a declaration with his signature on it. He doesn't have to make any showing. There are no requirements that have to be met. He just says there's a national emergency.
KEITH: That's right. The first step is shockingly easy.
GOITEIN: There aren't a lot of legal limits on his ability to do that, frankly, even if there isn't a real emergency happening.
KEITH: But Goitein argues it would be an abuse of power.
GOITEIN: Needless to say, emergency powers are intended to be used for emergencies, not to settle political disputes or to shortcut the political process.
KEITH: The second step, once an emergency is declared, Goitein says the president gets access to special powers granted by Congress over the years. Trump's lawyers would pick from about 100 laws to justify using the military to build a barrier along the southern border. But she says none of the statutes are a perfect fit. Bruce Ackerman at Yale Law School cites different laws and legal precedent to argue that the military can't be used that way.
BRUCE ACKERMAN: They would have to choose between a obeying the law or obeying the commander in chief. That choice represents a profound crisis.
KEITH: There is another precedent Ackerman cites from the Bush administration. After Hurricane Katrina, Congress passed a law allowing the military to go in. But then in 2008, they had second thoughts.
ACKERMAN: They said, oh, no, that's really a very dangerous precedent to allow the military simply to intervene whenever the president declares a state of emergency, and they repealed it.
KEITH: Democratic Congressman Adam Smith chairs the House Armed Services Committee, and he earned some unintended praise from the president for saying he could declare an emergency.
ADAM SMITH: The honest answer to the question could the president do this is yes. There'd be a fight afterwards, but he could, which is why I think what we need to emphasize is how wrong it would be for him to do it. It's bad policy.
KEITH: There would certainly be backlash in Congress and not just from Democrats. They could try to reverse the president's action. Court challenges are a sure thing, which means wall construction could hit a wall. Tamara Keith, NPR News.