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What happened to the self-service passport kiosk? The mobile passport line used to allow me to speed through customs. I don't know if I have to wait to show someone my passport.

Milena Rodban, 36, a geopolitics risk consultant, was appalled to find herself standing among thousands of people at Chicago O'Hare International Airport in August because the mobile passport app did not work. She convinced many of her friends to download the app because she was so happy with the way the code was generated.

There are a number of theories to explain the disappearance of mobile passport lines. Interviews with customs agents, airport officials, contractors and a review of government budget and privacy documents show that the U.S. Customs and Border Protection prioritized a new facial recognition system over other systems. In April, the C.B.P. quietly reached its goal of installing cameras next to customs officers in every international airport in the U.S., with the goal of checking virtually all incoming travelers by face, and building a related tool to spot foreign nationals lacking proper visas when they

Larry Panetta is the director of the biometric entry/exit program transformation.

The kiosks weren't able to verify faces. The mobile passport system will not be phased out, but the allocation of resources to it temporarily became less of a priority in some airports.

According to officials, the use of facial-recognition software will improve efficiency and security at ports of entry. Civil Liberties and digital privacy groups said that the changes represent fundamental threats to privacy.

ImageA passenger stands before a screen that shows an image of her face, while an airport employee checks her identity on another computer screen.
A woman boarding a flight to Copenhagen goes through the facial verification process at Dulles International Airport near Washington, D.C.Credit...Jim Watson/Agence France-Presse — Getty Images
A passenger stands before a screen that shows an image of her face, while an airport employee checks her identity on another computer screen.

It may have seemed like they were.

Americans returning to the U.S. from abroad over the past decade probably encountered a self-service kiosk. There were some that had a curve. The others had retro glowstick-esque lights. The devices allowed non-U.S. citizens from countries approved for self-service lines to give fingerprints.

The kiosks made their way into airports all over the country. They were praised for their speed.

The kiosks became less appealing to C.B.P. officials as they became more eager to do more with facial verification. They didn't analyze the photos they took.

The director of C.B.P. field operations in New York said that there was no way to determine if the individual was the true bearer of the passport.

According to C.B.P. officials, reprogramming the machines to do more made logistical and security headaches.

The agency started to install cameras in officers booths. The congressional mandate was spurred by the 9/11 attacks. The agency was ordered to create a system for foreigners. A 2016 bill allocating money that had to be used by 2027 and an order from Donald Trump contained within his ban on visitors from many Muslim countries sped up the process.

Matthew Davies is the executive director of the C.B.P.'s admissibility and passenger programs. There was no one who wanted to clean the kiosks. Most airports have removed them. Mr. Davies said they would all be gone by the year 2023.

It's sort of. The mobile passport program is here to stay, even though lines are getting added to some airports and removed from others, according to the executive vice president of the Airports Council International-North America.

The mobile system is an alternative to the Global Entry system for people who haven't heard of it. If you want to use Global Entry, you need to apply for $100. You need to look for a Global Entry kiosk when you arrive. They are being transitioned to facial verification.

There is no fee with the mobile passport system. Travelers use an app to input their passport information They look for a mobile passport line when they arrive.

Mr. Davies said that some locations felt that the C.B.P.'s facial comparison system would be quicker.

Some airports may have phased them out while making them more compatible. The facial comparison program has been used by the mobile passport system.

C.B.P. officials say that 85 percent of visitors arriving from abroad are verified by face. According to Mr. Panetta, 100 percent of flights will be processed this way by the end of the three year period.

If you are over the age of 14, a camera takes a picture of you. Americans can opt out, while foreign nationals have to. Critics say that the agency hasn't made it clear that you can ask an agent to confirm your identity. The alternative was written on a piece of paper taped to the side of the customs booth at JFK. Travelers over the age of 80 aren't required to participate in the exemption.

The photo should be thrown out within 12 hours if you are a U.S. citizen. The photo goes to the Department of Homeland Security if you are not a citizen. The need to give fingerprints again is eliminated if foreign nationals have previously provided them.

All faces are checked against a collection of passport, visa and airport photos that C.B.P. has prepared. Travelers might not have to give up their passport if the new photo matches the old one. If it doesn't, the agent is supposed to compare the new photo to the photo stored in a chip within most passports The agent might suspect that the traveler is using a stolen, borrowed or counterfeit passport.

There are legitimate reasons for a failed attempt. Black and brown faces are more deceptive than other faces due to age and light. At a Congressional hearing in July, Nicol Turner Lee, the director of the Center for Technology Innovation at the Brookings Institution, said that at least three Black men have been arrested because of faulty facial recognition.

When the program is used with departing passengers, airlines take pictures of departing passengers to see if they match an existing photo on file. If there is no match, the C.B.P. will know that the person entered the country without a visa.

The new system streamlines and fortifies the process of entering the United States while also helping identify foreign travelers without visas on the way out, according to proponents of the new system.

C.B.P. representatives said the system stopped around 1,600 people from entering the country through airports and land borders.

It could prevent what it could not.

"We don't want another 9/11 in this country," said Mr. Russo, who noted that the system frees up officers to focus on asking the important questions that help keep terrorists and drug traffickers out of the country."

According to a C.B.P. report, the tool has been used to alert the agency to 100,000 overstays.

I agree.

Jeramie D. Scott, the senior counsel at the Electronic Privacy Information Center, called Simplified Arrival a "powerful and dangerous tool" that requires more federal oversight. He argued in an interview that the program is already overstepping because it uses facial recognition on U.S. citizens and fills the database with Americans' passports. According to the C.B.P. officials, Americans can opt out of passport fraud.

The American Civil Liberties Union believes in the same thing. C.B.P. should not be using this technology at airports because it would fundamentally change American society, according to a senior staff attorney for the organization.

Many civil liberties, digital privacy and immigrant rights groups have raised concerns that the rapidly expanding HART database could be used to monitor people and increase deportations. The database is expected to contain information from other federal and local agencies and foreign governments for some travelers. Around 40 organizations urged an Amazon subsidiary to not host the database in the cloud.

It might seem odd to phase out self-service kiosks during a labor shortage. The C.B.P. officials said that the new system altered their role. Travelers obtained a printout from the kiosk and officers were still responsible for verification. Paper customs declarations are no longer required and officers can get a verbal answer based on what they want to ask.

It will be hard to assess efficiency until international travel recovers.

It is unlikely that biometrics will replace officers completely. Customs agents are required to interact with every person at the border.

He said that the technology is there, but that the law won't change.