Apple and the FBI return to Congress next week to continue their stoush over law enforcement access to encrypted devices.
The tech firm's general counsel, Bruce Sewell, and the FBI's executive assistant director for science and technology, Amy Hess, will testify on Tuesday (local time), in addition to other law enforcement officials and technology experts.
FBI director James Comey appeared before a separate congressional committee last month to defend his agency's request to force Apple's assistance in unlocking an iPhone linked to one of the San Bernardino shooters. Sewell also testified at that hearing.
The FBI dropped the San Bernardino case after it paid as-yet unnamed professional hackers to break into the iPhone, but that hasn't stopped the US Justice Department continuing with an appeal to make Apple help in an unrelated New York drug case.
Earlier this week, two US Senators released draft legislation that would empower courts to order technology companies to hand over data "in an intelligible format", even if encryption has rendered that data inaccessible to anyone other than the owner.
Security researchers and civil liberties advocates have heavily criticised the Bill, saying it amounts to a ban on strong encryption, which protects the overall security of the internet.