Story highlights Katie Fallow: Many citizens re-entering US subjected to cellphone searches and questions about their social media

Knight First Amendment Institute is suing to see government data on how, when, why, on whom this is being practiced

Katie Fallow is a senior attorney at the Knight First Amendment Institute at Columbia University. The opinions expressed in this commentary are hers.

(CNN) An engineer from NASA's Jet Propulsion Laboratory. A Wall Street Journal reporter and a French-American photojournalist. An independent filmmaker. An electronics salesman.

These are some of the many American citizens re-entering the country who have been subjected to searches of their cellphones and questioning about their social media.

Katie Fallow

Such invasions of travelers' private communications are extremely intrusive and have been conducted even when officials don't apparently have reason to think the person has done something wrong. And the government has lately increased the practice dramatically — even though recent legal decisions raise serious questions about its constitutionality.

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Because people keep ever more of their personal details on their phones and computers, it is particularly egregious that the government should claim some right to unfettered access to these devices simply because a person travels abroad.

On Monday, the Knight First Amendment Institute at Columbia University — whose mission is to defend free speech in the digital age — filed a lawsuit seeking to compel the government to release information on the number of travelers whose devices have been searched, the policies related to searching cellphones containing sensitive and confidential information, and the findings of internal audits about the device search program.

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