The American Civil Liberties Union and the Electronic Frontier Foundation sued the Department of Homeland Security on Wednesday for searching the phones and laptops of 11 plaintiffs at the US border without a warrant.

The group of plaintiffs includes 10 US citizens and one lawful permanent resident, several of whom are Muslims or people of color. Among the group are journalists, a veteran and a NASA engineer. All were reentering the US following business or personal travel. Some plaintiffs had their devices confiscated for weeks or months. None were accused of wrongdoing following the searches.

"People are traveling with electronic devices that have an unprecedented amount of highly personal information on them," said EFF staff attorney Sophia Cope. "The privacy interests in a smartphone are significantly greater than the privacy interests in a piece of luggage. The Constitution requires that the government must meet a higher burden to get access to travelers' personal information."

Border electronic device searches have been increasing over the last few years. Officers searched approximately 15,000 electronic devices in the first half of fiscal year 2017, according to US Customs and Border Protection, almost three times the total number of searches conducted in 2015. In 2016, a total of 19,033 searches were conducted.

CBP, which is a Department of Homeland Security agency, states on its website that "no court has concluded that the border search of electronic devices requires a warrant." But many travelers, including the plaintiffs in this case, have cited concerns about officers reading private emails and messages on their phones and laptops.

CBP spokeswoman Jennifer Gabris said the agency doesn't comment on pending litigation, but noted that Homeland Security's actions are consistent with its responsibility to protect the country and enforce laws at the borders. She said all people, baggage and merchandise arriving in or leaving the US are subject to search.

"We're not saying that CBP can't ever search someone's device, but they need to have probable cause that the device contains evidence that the traveler has committed a customs or immigration violation," Cope said.

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