Late one night last April, someone with a gun came to the door of the Baton Rouge apartment where Brittney Mills lived with her 10-year-old daughter, NBC News reported.
Mills, 29 and nearly nine months pregnant, was a cautious person, her family says — she would not have answered that knock for someone she didn't know.
No one is sure what happened next, except that Mills was shot dead. The answer of who killed the at-home nurse and an industrial safety technician may lie in her iPhone, which lies useless amid an escalating battle between Apple and law enforcement over access to consumers' encrypted data.
Investigators turned to the victim's iPhone, where they hoped phone records, text messages and a rumored diary would contain clues.
When that failed, they obtained a search warrant for Mills' iCloud data. But she hadn't backed up her phone for months. So they got warrant for the phone itself.
The FBI's fight over the San Bernardino phone had brought national attention to the privacy debate. But the Mills case illustrates how the dilemma tangles up local authorities as well.