Extended questions, excavations of his social networks and emails, so many nightmares told by travelers going to the United States. How to secure a trip to the United States without digital clashes? The show on talk about it asked for advice from Stéphane Koch, information security expert.
The case of a Zurich teacher detained for 24 hours when she arrived at New York airport had struck the spirits in April: her phone had been searched by American customs officials, then she was denied entry into the territory.
Do American customs officials have the right to search our computers and smartphones? “Yes, they have practically all rights, especially for people who are not of American nationality,” replied Stéphane Koch, expert in digital strategy and information security, in the program we talk about it on June 25, 2025. “When we enter the United States, we can be subject to this type of excavation without obvious reason. We are then forced to provide his passwords and access to her phone.”
Travel the light smartphone
Stéphane Koch compares the data on his peripherals with his luggage: “When you make your suitcase, you don’t take all your apartment with you. This is the same with personal data and peripherals.” The specialist recommends choosing the data you take with you by making backups before leaving. “It is also possible to take a phone or computer only dedicated to the trip.”
What if you store your data on a cloud? “During the excavation, the telephone should normally be in plane mode, because the customs services are not supposed to access information remotely,” says Stéphane Koch, which recalls that it is possible to uninstall applications before leaving as a precaution.
Clean your social networks
“We must pay attention to the criticisms that have been issued, in particular on the Trump administration. It would seem that in some cases, this could be a reason for dismissal,” explains Stéphane Koch. Should we erase all the compromising posts? “In principle of precaution, it is preferable to do it.”
Can we protect ourselves using pseudonyms? “Not specifically. It’s been a long time since social networks are monitored. On the other hand, we do not have to indicate them in the ESTA form. The Swiss are entitled to a simplified approach. On the other hand, if it is a visa request, we are legally obliged to indicate the social networks on which we have been in the past five years.”
Warn his loved ones
Stéphane Koch advises to warn his relatives of his approximate arrival time in the United States. The latter may, if necessary contact the Embassy or the Federal Department of Foreign Affairs (DFAE). The specialist also advises to install the DFAE Travel Admin Application, which allows to warn an emergency contact.
Encrypt your data
“There is the passage of the border, but not only. We are in an area where we do not have a total control, in hotels for example. Our peripherals can be stolen or hacked,” explains Stéphane Koch, who recommends ensuring the encryption of data from his devices. “Some data […] Like medical data, could be on our peripherals. Exchange data with lawyers, however, are protected by law in the United States and must be mentioned. “
Software to encrypt data like Veracrypt allow you to store your confidential data. “When I arrived at customs, I can always communicate without lying.” The specialist recommends getting in a plausible denial situation, that is to say being able to defend himself credible so as not to arouse distrust. “I have encryption software and I can give access to this virtual room to customs officials. However, I have a second electronic key that gives me access to a hidden room. This cannot know,” concludes Stéphane Koch.
Radio subject: Mathieu Truffer
Adaptation Web: Myriam Semani
