Earlier this week at least two US Customs and Border Protection officers boarded a domestic Delta Air Lines flight from San Francisco when it arrived at JFK Airport in New York, stood at the doorway as passengers disembarked, and “requested” that each passenger hand over their identification “documents”.

CBP says that this was a “request“.  One passenger told Rolling Stone, “the Delta flight attendant alerted passengers, ‘You’ll need to show your papers to agents waiting outside the door.'” As shown in photos posted to Twitter by passengers here and here, the agents appear to have been between the passengers they were questioning and the exit, closing them in so that they couldn’t have left.

It’s often unclear whether a statement of what law enforcement officers “need” is a request or a demand. Another passenger, a photo editor for Vice News,  says passengers were given an order, not a potentially ambiguous statement of “need”: “We were told we couldn’t disembark without showing our ‘documents.'”

Many air travelers in the US have become inured to requests or demands for ID documents by airline clerks and TSA checkpoint staff and contractors before they are allowed to board domestic flights. But the presence of Customs and Border Protection officers on a domestic flight, and ID checks after an otherwise uneventful flight, have prompted many questions.

Is this normal? Is this legal? Should it be legal? And what should you do if this happens to you?

We think any demand for ID from passengers traveling or seeking to travel by common carrier within the US should be considered per se unconstitutional if made by or at the behest of the government, and a violation of the carrier’s duty as a common carrier if made by or at the behest of the carrier.

Unfortunately, while there would be a basis for a Constitutional challenge to the CBP’s actions in this incident, courts might not uphold it on the basis of current case law.  And passengers who did show ID would probably be found to have no standing to challenge what might have happened if they had declined to show or hand over ID or had tried to leave the plane without doing so.

While CBP officers rarely board domestic flights, they have explicit (if questionably Constitutional) statutory authority to do so to search for aliens as part of their authority over the “border” and its vicinity.  Title 8 U.S. Code Section 1357 (a)(3)  provides:

Any officer or employee of the Service authorized under regulations prescribed by the Attorney General shall have power without warrant … within a reasonable distance from any external boundary of the United States, to board and search for aliens … any railway car, aircraft, conveyance, or vehicle.

Note that this statute makes no distinction between aircraft. It applies to all aircraft — private, commercial, government, or military — and regardless of whether they are parked, arriving, or departing or whether they have been, or are intended to be, operated domestically or internationally.

Regulations at Title 8 C.F.R. Section 287.1(a)(2) (also of questionable Constitutionality) define these terms and distances as follows:

(a)(1)External boundary. The term external boundary, as used in section 287(a)(3) of the Act, means the land boundaries and the territorial sea of the United States extending 12 nautical miles from the baselines of the United States determined in accordance with international law.

(2)Reasonable distance. The term reasonable distance, as used in section 287(a) (3) of the Act, means within 100 air miles from any external boundary of the United States or any shorter distance which may be fixed by the chief patrol agent for CBP, or the special agent in charge for ICE, or, so far as the power to board and search aircraft is concerned any distance fixed pursuant to paragraph (b) of this section.

(b)Reasonable distance; fixing by chief patrol agents and special agents in charge. In fixing distances not exceeding 100 air miles pursuant to paragraph (a) of this section, chief patrol agents and special agents in charge shall take into consideration topography, confluence of arteries of transportation leading from external boundaries, density of population, possible inconvenience to the traveling public, types of conveyances used, and reliable information as to movements of persons effecting illegal entry into the United States.

Like the areas where most of the US population lives, Kennedy Airport (JFK) is within 100 miles of the US border, as defined in relevant part by these regulations as the 12-mile limit between US territory and international waters in the Atlantic Ocean.

CBP claims that its officers’ boarding of Delta Flight 1583 when it arrived in New York from San Francisco on February 22nd was to “search for aliens”. So both the location (any aircraft within US jurisdiction and within 100 miles of international waters) and the purpose (to search for aliens) of the boarding and search were clearly within the authority purportedly granted by this statute and these implementing regulations.

If if surprises you that CBP has or claims this sort of authority to board a domestic flight on arrival, than perhaps you should be more concerned about other aspects of the “border search” authority that CBP has been given by Congress through this statute and has claimed for itself by promulgating these regulations.

Boarding and questioning of passengers on domestic flights is relatively uncommon, perhaps because CBP realizes that airline passengers are, in general, relatively privileged, empowered, and likely to complain or even sue. But CBP and other DHS officers and other Federal, state, and local law enforcement participants in “Joint Task Forces” routinely board and question passengers on domestic trains and buses, using “border proximity” (up to 100 miles) and/or intimidated/coerced “consent” as the basis for searches nor just for undocumented aliens but for drugs, cash, and other property that can profitably be seized and expropriated under “civil forfeiture” laws.

In recent years, independent reports by the DEA Office of Inspector General have criticized these practices on Amtrak trains within the US and at domestic airports. (Our 2014 FOIA request for information about Amtrak collaboration with CBP and other law enforcement agencies remains pending. This week Amtrak again revised its estimated date for completing its response to this FOIA request, this time to May 2017.)

Judicial review of the Constitutionality of searches and requests/demands for ID in the vicinity of the border would probably be based on prior decisions regarding detention and questioning about immigration status at highway checkpoints and in workplaces, and about “consent” to questioning and search in the context of bus boardings by police. There’s much more extensive case law about onboard questioning and searches of bus passengers than about passengers on trains or airplanes.

The Supreme Court has rightly or wrongly (we think wrongly) upheld suspicionless stops and questioning of domestic travelers on public roads “near” US borders  provided that the detention is “brief” and the questioning is limited to citizenship or immigration status.  All of Interstate 5 on the West Coast, I-95 on the East Coast , and I-10 across the southern US, among other arterial highways, are within 100 miles of US land or ocean borders.

Courts have found that travelers can be briefly detained for questioning, although the meaning of “brief” is unclear. But we are not aware of any case law upholding a requirement to answer any questions or produce any documents in the absence of reasonable articulable and individualized suspicion, or holding that failure to answer questions or produce documents is, in itself, grounds for arrest or indefinite detention.

As we have noted in recent cases, courts have consistently held that pedestrians cannot lawfully be required to identify themselves in the absence of reasonable suspicion that they have committed some specific crime. We think demands for ID from passengers traveling by common carrier should have the same rights as travelers on public rights of way.

A demand to hand over ID credentials, like any demand to produce and hand over documents or other items not in plain view, is a search. Except in the context of highway checkpoints where there is an unarguable “stop” and detention, law enforcement agencies and officers typically defend dragnet sweeps by claiming that those who were questioned weren’t really detained, but were “free to leave” at any time and “consented” to be searched.

The Supreme Court has decided that the the validity of “consent” to a suspicionless search of bus passengers and their belongings depends on whether “a reasonable person would believe that he or she is not ‘free to leave.'”

In the case of Delta Flight 1583, we don’t know what would have happened if a passenger declined to answer questions, declined to show ID, or tried to walk past the CBP officers and leave the plane. Some of the passengers might perfectly legally have passed through TSA checkpoints and boarded the flight without having or showing any ID, as people do every day.

It’s unclear whether a court would find that, in the circumstances depicted in this photo, a  reasonable person would have felt free to leave without answering questions or showing ID documents.

The Supreme Court has also ruled that law enforcement officers questioning and searching passengers on a common carrier are not required to tell you whether you have to comply with their “requests”, or to tell you whether you are free to leave.

The only way to find out whether you are required to answer questions is to stand mute. The only way to find out if you are required to produce or hand over documents is to keep them out of sight and not to hand over or open your bags or put your hands in your pockets.  The only way to find out if you are free to leave is to walk away. The only way to find out whether government agents will allow you to exercise your rights is to exercise your rights. Only then are you likely to be found to have standing to challenge any infringement of your rights.

So far as we can tell, all the passengers on Delta Flight 1583 produced and handed over documents that the CBP officers found acceptable, and were then allowed to leave. So we will probably never know whether the courts would have upheld the legality of the CBP officers’ actions.