– Barbara Mills, a retired nurse in Baton Rouge, La., has been tormented for seven months by questions no mother should have to ask: Who killed her 29-year-old daughter Brittney in cold blood, and why is new privacy technology allowed to potentially stop the police from finding out?

Brittney’s murder is only one of many serious crimes in the United States and Canada that could go unsolved because Apple and Google are deploying strong encryption on cellphones and messaging applications that even the cops can’t break through. The advanced privacy technology is designed to keep all prying eyes away from files or messages if the correct password is not used.

Even a law-abiding citizen who loses a loved one, like Barbara Mills, is now unable to recover files stored on the fully encrypted phones if they didn’t obtain their relative’s password in advance.

Brittney Mills, a single mother who was eight months pregnant with her second child, opened her apartment door late one evening last April. Police believe she knew the killer. She refused to let the still unknown person borrow her car, they believe, and was shot shortly after. Her nearly full-term baby boy clung to life for a week before dying. Mills leaves behind a daughter, now 10 years old.

Police are convinced clues to the murderer’s identity lie inside the victim’s iPhone. “She did say she had a diary in her phone and that everything negative that happened to her was in that diary,” her mom said. “If that phone could help solve that case then I think law enforcement and law enforcement alone should be able to go into those phones and access whatever it is they need to access. You have two murders here. Not one, but two.”

But like many consumers, Brittney Mills never shared her phone’s password with anyone. Baton Rouge authorities obtained her family’s permission to look inside of it but could not get past Apple’s encryption even after reaching out to the FBI and the Secret Service for help.

Investigators were able to successfully retrieve a trove of information from Brittney’s Apple iCloud account, but they say the last time a backup of her phone occurred was months before the crime, meaning her most recent communications and activities remain unknown to police, and her personal diary was not included in any of the files recovered from the iCloud backup.

“I’m at a dead end right now and I need that information to make sure we fully investigate this case and try to bring justice to this family and our community,” East Baton Rouge District Attorney Hillar Moore said.