President Donald Trump knew his emergency declaration on the southern border would be challenged in court, and already 16 states, a number of leftwing organizations, and even landowners on the border are following suit. But one constitutional lawyer believes Trump will get his wall built.

This assessment came in an interview on taxpayer-funded and leftist National Public Radio’s (NPR) Weekend Edition Sunday, where the host questioned Jonathan Turley, a liberal law professor at George Washington University, about the legal challenges Trump will face.

“We just heard about one lawsuit being brought against the president by landowners and other stakeholders along the southern border. Do they have a case?” Lulu Garcia-Navarro asked Turley.

“Well, they have a case, but I’m afraid I don’t believe they have a particularly strong case,” Turley responded.

Turley explained that the National Emergencies Act enacted in 1976 “gave a president virtually unfettered authority.”

“In fact, it really doesn’t even define what an emergency is,” Turley said.

Turley also explained that Congress could look at two things if they want to stop the president: the act itself or the source of funding Trump is using.

But, Turley said, even challenging the funding might be “a long row to hoe because [Congress] gave the president over a billion dollars and he’s now identified at least three sources of largely undedicated funds that he can use.”

“Even if you knock out half of those, he’s still over $5 billion,” Turley said.

Garia-Navarro pressed Turley, saying — as many leftist media are highlighting — that Trump said he didn’t have to go with this plan but wanted to speed up the process and get the wall built.

Turley pointed out that many have lobbied Congress to change the act, but that has not happened.

“And this is sort of the chickens coming home to roost,” Turley said. “They gave him a stature with unfettered authority and gave him billions of dollars with limited conditions, and he’ll use both of those.”

“I guess the big question is, how friendly will the courts be to these cases, because presidential authority is an open question?” Garcia-Navarro said.

Turley explained that Congress could, with a majority vote in both chambers, rescind the act, but Trump could still veto that.

“So you do need a supermajority,” Turley said. “And the odds are they probably don’t have the votes for that.”

Garcia-Navarro asked Turley for a prediction.

“I think that he’s going to prevail,” Turley said. “And if they challenge him on his right to declare an emergency, I think that will be a spectacular failure.”

“They’ll have to focus on the source of the funds,” Turley said. “But I don’t think that’s going to get them all the way they need to go to stop this construction.”

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