During arguments considering whether police need to show probable cause and obtain a warrant before getting a person’s cellphone location history, two members of a Ninth Circuit panel—Judges Mary McKeown and Jay Bybee—expressed concern over the growing frequency and precision with which cellular providers can track their customers.
However, the third panel member, Senior Judge J. Clifford Wallace, pointed out that four other circuits that considered the same question held that Fourth Amendment protections don’t apply to regular business records that mobile phone companies keep that track customers’ location.
