CONGRESS MUST consider it a priority to pass legislation in the next few months reauthorizing the U.S. intelligence agencies to eavesdrop without a court warrant on communications of foreigners who are located overseas, including at times their exchanges with Americans. The legislation, Section 702 of the Foreign Intelligence Surveillance Act, is of bedrock importance to the National Security Agency. Still, while giving the law a new lease, Congress ought to insist on additional protections for Americans in the use of the Section 702 database.

Under existing law, the Federal Bureau of Investigation can query Section 702 information for emails and phone-call transcripts of Americans suspected of a crime, without obtaining a warrant. This is a loophole allowing the FBI to go after information that, if sought from other sources, would require a warrant. A bipartisan group of lawmakers from the House Judiciary Committee, led by Chairman Bob Goodlatte (R-Va.) and Vice Chairman John Conyers Jr. (D-Mich.), have proposed a reauthorization for six years that would effectively close this back door. They would allow the FBI to make such queries only when a warrant was in hand. The limits they seek would apply only to criminal suspects and would not restrict queries by the intelligence agencies for countering espionage, proliferation or terrorism, among other things.

By law, the NSA can target the communications of foreigners overseas if they fall into broad court- ­approved categories of foreign intelligence collection. The NSA targeted 106,000 such foreigners in 2016, Post reporter Ellen Nakashima reported. For each target, all the people they communicated with were also swept up in "incidental" collection. Congress has been unable to get the intelligence community to disclose even a rough estimate of how many Americans' communications are caught up in this net, and some reporting of the scope ought to be required as part of the reauthorization.

Understandably, the FBI would like to keep the unfettered authority to query the Section 702 database. But to do so would expose Americans' information to surveillance without a warrant, undermining Fourth Amendment protections against unreasonable searches. If the investigation is serious enough, the government ought to be able to create a mechanism that would provide the most expeditious decision on a warrant. Other solutions are possible: Rep. Adam B. Schiff (D-Calif.) proposes not restricting FBI searches but instead limiting their admissability in court.

The Trump administration has been pressing for a clean bill that would make Section 702 permanent without any changes. This seems unwise. After all the uproar in recent years following the Edward Snowden disclosures, the intelligence community should want a system that is firmly anchored in the trust of the American people and unambiguously endorsed by Congress. Privacy advocates want even tighter restrictions in the law, and we trust Congress will examine these ideas. But the goal should be to put this entire matter on a sustainable, bipartisan foundation so that the intelligence agencies can pursue their vital tasks knowing the rules.