Sens. Rand Paul (R-Ky.) and Ron Wyden (D-Ore.) are expected to introduce bipartisan legislation Tuesday to prohibit warrantless searches of digital surveillance of Americans collected incidentally via Section 702 of the Foreign Intelligence Surveillance Act (FISA).

The information in question is data swept up in the process of FISA spying on foreigners located outside the United States. The content about Americans is saved, and that database is then available for warrantless searches by federal agents investigating matters unconnected to the original spying goal.

This type of FISA surveillance is what President Trump clumsily accused the Obama administration of using on Trump Tower during the 2016 election. Experts say it is plausible the feds "may have come upon Trump Tower phone calls if a targeted foreign agent was on the other end of the line" and that agent was subject to FISA spying.

Section 702 is due to expire at the end of this year, and the Senate will also hold closed-door committee hearings Tuesday about a measure to reauthorize it. Paul and Wyden argue a straight reauthorization will perpetuate grave civil liberties abuses in violation of the Fourth Amendment. "This legislation will have enormous impact on the security, liberty, and constitutional rights of the American people," Wyden wrote Monday. "The public has therefore taken a keen interest in the outcome of this mark-up and in specific proposed reforms to Section 702." Bonnie Kristian