Senators Rand Paul (R-Ky.) and Ron Wyden (D-Or.) have long been two of the most outspoken privacy protection advocates in the U.S. Senate, and they are now introducing new legislation that would require law enforcement officials to get a warrant before going through American citizens’ phones or demanding their passwords when re-entering the country.

The Protecting Data at the Border Act would make it illegal for border or law enforcement officials to search or seize U.S. citizens data via their phones or other devices without probable cause. Border or state agents opening phones to flip through pictures or other information as part of a “manual search” would also be covered in this new legislation.

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Sen. Paul has spent years sounding the alarm that U.S. citizens constitutional rights are constantly violated due to an increasingly intrusive and largely unrestricted mass surveillance state, and Wyden has often been a co-sponsor or supporter of legislation that would rein in such practices. This new legislation is the duo’s latest effort to protect constitutional privacy rights.

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“Americans’ Constitutional rights shouldn’t disappear at the border,” Senator Ron Wyden told BuzzFeed News. “By requiring a warrant to search Americans’ devices and prohibiting unreasonable delay, this bill makes sure that border agents are focused on criminals and terrorists instead of wasting their time thumbing through innocent Americans’ personal photos and other data.”

“A border stop shouldn’t be an excuse for extreme surveillance such as downloading the entire contents of your phone,” Greg Nojeim told Reuters. Nojeim is the senior counsel at the Center for Democracy & Technology, a civil liberties organization that supports the bill.

The bipartisan legislation is also being introduced in the House by Republican Rep. Blake Farenthold and Democrat Rep. Jared Polis.