Does the US President have the legal authority to unilaterally close the country’s borders?



President Trump recently tweeted that he may close the country’s southern border if Congress does not appropriate the funds to build a border wall.

... We build a Wall or close the Southern Border ...

– @realDonaldTrump (Tweet 1 and Tweet 2)

So, does the executive branch have the legal authority to either partially or fully close the country’s borders?


Posted 2018-12-29T02:11:08.077

Reputation: 41 470

2Even tho the answer seems to be yes (see @Michael_B's answer) -- there is a "we" in the quote, so why assume that it will be closed unilaterally? – user45891 – 2018-12-29T16:20:48.153

@user45891 - Michael B provides compelling references as it applies to Presidential authority to bar aliens, but there seems to be no such authority to close the border beyond that. Until the President provides some detail to his tweet we can only guess (aka speculate) about the threat. – BobE – 2018-12-30T03:28:56.587

@user45891 I assumed "we" to refer to the Trump administration or, simply, the executive branch. – Panda – 2018-12-30T05:12:34.340



The term "close the southern border" is quite broad and has many potential ramifications.

Would such a directive apply to citizens? Legal residents? Commercial vehicles?

Does he mean closing established ports of entry?

Or, when he says "build a wall or close the southern border", does he actually mean the same thing? After all, building a border wall could be interpreted as closing the border.

President Trump is no stranger to broad, sweeping and contradictory terms. For example, he promised repeatedly during his campaign that "Mexico will pay for the wall". (So why is he even asking Congress for funding? That's a whole other question.)

Apparently, payment for the wall is coming, not through a check from the Mexican treasury or deductions in foreign aid, but through improved trade relations negotiated in the United States–Mexico–Canada Agreement (USMCA).

Without the details, most of his "close the southern border" statement is undecipherable.

Considering that the President is focused on illegal immigration, let's assume that "close the border" applies only to non-citizens crossing the border without authorization.

This is interesting because many of these people are already avoiding the established ports of entry. They are crossing wherever they can, regardless of how remote and treacherous the path may be. This is, after all, why the President wants to build a border wall.

So the benefits of closing the border, in terms of curtailing illegal immigration, are not clear.

Legally, the President has the authority to "suspend the entry of all aliens" if he/she finds the entry of aliens "detrimental to the interests of the United States". (The IRS defines "aliens" as any non-citizen.)

United States Code > Title 8 > Chapter 12 > Section 1182(f) "Inadmissable Aliens" reads:

Suspension of entry or imposition of restrictions by President

Whenever the President finds that the entry of any aliens or of any class of aliens into the United States would be detrimental to the interests of the United States, he may by proclamation, and for such period as he shall deem necessary, suspend the entry of all aliens or any class of aliens as immigrants or nonimmigrants, or impose on the entry of aliens any restrictions he may deem to be appropriate.

In 2017, the U.S. Supreme Court affirmed this authority in Trump v. Hawaii.

Here's an excerpt from Chief Justice John Roberts' majority opinion:

By its terms, §1182(f) exudes deference to the President in every clause. It entrusts to the President the decisions whether and when to suspend entry (“[w]henever [he] finds that the entry” of aliens “would be detrimental” to the national interest); whose entry to suspend (“all aliens or any class of aliens”); for how long (“for such period as he shall deem necessary”); and on what conditions (“any restrictions he may deem to be appropriate”).

It is therefore unsurprising that we have previously observed that §1182(f) vests the President with “ample power” to impose entry restrictions in addition to those elsewhere enumerated in the INA (finding it “perfectly clear” that the President could “establish a naval blockade” to prevent illegal migrants from entering the United States).

The sole prerequisite set forth in §1182(f) is that the President “find[]” that the entry of the covered aliens “would be detrimental to the interests of the United States.”

Michael Benjamin

Posted 2018-12-29T02:11:08.077

Reputation: 10 142

6We seem to be missing a check and/or balance there. Scary. – Jared Smith – 2018-12-29T02:39:25.767

6While I agree that the Pres has the authority to close the border to aliens, his statement does not say 'close to aliens'. Taken literally, his statement can be taken that the border will be closed to all crossings. (including those US citizens who are on vacation or conducting business) – BobE – 2018-12-29T04:44:24.477

6@Jared Smith: We do have a couple. Impeachment, and the 25th Amendment. – jamesqf – 2018-12-29T05:07:39.497

1@janesqf : Impeachment requires some form of crime, as far as I understand it. Under what sort of circumstance might closing the border or abusing the border power constitute a crime? – The_Sympathizer – 2018-12-29T05:31:56.787

5@The_Sympathizer “high crimes and misdemeanors” is the Constitution’s phrase, which has history in English law and can cover a whole host of things—anywhere from treason to “unbecoming conduct” or “chronic intoxication,” according to Wikipedia. Benjamin Franklin famously referred to the impeachment clause as a remedy to a president who has “rendered himself obnoxious,” though of course that phrasing is not in the Constitution. Ultimately, what qualifies as grounds for impeachment is wholly up to the House of Representatives, and what qualifies as grounds for removal is up to the Senate. – KRyan – 2018-12-29T05:45:23.980

1I don't think Trump was just talking about immigration here. He's other statements on Twitter on this issue, IMO, make it clear that he's also talking about commerce, namely he believes that closing the border to imports and exports is both a way to "get around" the trade deficit resulting from NAFTA and tank the economy until the Democrats agree to his funding requests. I believe, though, that the answer is still "Yes", if temporarily, but I don't have any citations to prove it. – KutuluMike – 2018-12-29T07:49:13.570

9@JaredSmith: This is a law, so the primary check and/or balance is that Congress can change the law -- overriding, if necessary, Trump's veto. – ruakh – 2018-12-29T08:24:25.070

1This answer's very well supported with respect to the issue of closing the border to aliens, though is there any argument for why this might extend to closing the border entirely? Or, is Trump only threatening to close the border to aliens and not, say, US citizens moving trade goods? (Haven't looked into the details too much, just recall a news story claiming that shutting down the border could result in lots of economic losses, so I'd assumed that the threat included to block trade routes too.) – Nat – 2018-12-29T09:05:09.950

3I've downvoted this answer because of the nature of snark that has been inserted into it. The answer could be built from an unbiased view, improving its overall acceptance. – Drunk Cynic – 2018-12-29T15:27:55.610

1Please specify what you mean by "snark" and where you see bias (and in what diection). Thank you. @Drunk Cynic – Michael Benjamin – 2018-12-29T15:39:44.077

1No where in the answer do you address if the President has the authority to unilaterally shut down the Border to all traffic. The closest it comes is "he can stop the entry of aliens." – Drunk Cynic – 2018-12-29T15:50:17.590

3@Drunk Cynic - the best answer (part of Michael B's answer) is "Without the details, most of his "close the southern border" statement is undecipherable." What you should have objected to was the original question and it's placement in Politics versus Law. – BobE – 2018-12-29T16:18:30.107

@DrunkCynic, The answer originally contained only the content (you highlighted) beginning with "Legally, the President...". The purely legal argument seemed sufficient to me on my initial readings of the question. Then I slept on it. This morning I realized that closing the borders would have an impact beyond just illegal immigrants. So I made some additions. I assure you, there is no intentional snark or bias here. Just an effort to address other possible interpretations of the President's remark. – Michael Benjamin – 2018-12-29T16:31:57.333


The power to designate ports of entry belongs either to the president or to subordinates. See for example 19 USC 2:

The President is authorized from time to time, as the exigencies of the service may require, to rearrange, by consolidation or otherwise, the several customs-collection districts and to discontinue ports of entry by abolishing the same or establishing others in their stead.

It follows that the president could close the southern border by removing all the ports of entry on the southern border, leaving no legally designated place to cross.


Posted 2018-12-29T02:11:08.077

Reputation: 9 434