NSA
A helicopter view of the National Security Agency in Fort Meade, Maryland BRENDAN SMIALOWSKI/AFP/Getty Images

A group of US House lawmakers are introducing new legislation that would impose restrictions on the National Security Agency's warrantless internet surveillance powers - a move that will likely trigger a standoff with the administration of US President Donald Trump. The bill from the House Judiciary Committee will be formally introduced on Thursday (5 October) and would revise the government's foreign surveillance provision, known as Section 702 of the Foreign Intelligence Surveillance Act (FISA), before it expires on 31 December.

Section 702 aims to gather data on foreign spies, terrorists and other foreign targets overseas and allows US intelligence agencies to collect emails and phone calls of foreigners abroad from American internet and telecom giants without a warrant. However, the collection also "incidentally" scoops up data of US citizens who communicate with a foreign target of surveillance.

Civil rights advocates have long urged lawmakers to close the "backdoor search loophole" that allows federal investigators to access Americans' information that has been "incidentally" collected without a warrant, arguing that it violates Fourth Amendment protections against unlawful search and seizure.

The proposed legislation, called the US Liberty Act of 2017, would renew Section 702 for six years but require the FBI to obtain a warrant to review any data or communications when seeking evidence of a crime.

However, the restriction would not apply to requests of data pertaining to counterterrorism or counter-espionage. The bill will be introduced by Judiciary Committee chairman Bob Goodlatte and Ranking Member John Conyers.

Democratic Senator Ron Wyden and Republican Senator Rand Paul are also planning to introduce a bill that would require a warrant for all queries under Section 702 involving Americans' data.

The House Judiciary Committee's bill is expected to face stiff opposition from the Trump administration. Earlier this year, the White House and intelligence agencies backed another bill proposed by Republican senators to renew Section 702 without any changes and make it permanent.

The American Civil Liberties Union has argued that the proposed bill does not provide enough protections for US citizens.

"While the bill contains positive provisions that are an improvement over current practice, it falls short of what is needed to protect individuals from warrantless government surveillance under Section 702," Neema Singh Guliani, legislative counsel for the ACLU, said in a statement. "Its most glaring deficiency is that it only partially closes the so-called 'backdoor search loophole.'

"Those worried that current or future presidents will use Section 702 to spy on political opponents, surveil individuals based on false claims that their religion makes them a national security threat, or chill freedom of speech should be concerned that these reforms do not go far enough. We urge members of the House Judiciary Committee to strengthen this bill as it moves forward."