Members of Congress often deal with sensitive information, the disclosure of which could jeopardize national security. In a Sept. 22 letter, the American Civil Liberties Union urged the House and Senate Sergeants at Arms, who are responsible for congressional digital security, to provide secure communications technology to lawmakers and their staffs.

In the letter, the ACLU said that “ensuring the security of Congressional communications against all interception—whether by foreign governments, criminals, or even other branches of the U.S. government or rogue Congressional staffers—would promote both basic liberty interests and national security.”

Although services provided by wireless carriers aren’t secure, the ACLU pointed to other widely available smartphone applications that encrypt voice, video and text messages—such as Apple Inc.’s iMessage and Facetime, Facebook Inc.’s WhatsApp and Open Whisper Systems’ Signal.

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