That's why you're supposed to use law enforcement resources where you know it makes a difference. The FBI made this whole circus around this phone when everyone already knew they wouldn't found anything. But worst of all, they didn't even bother to check the metadata for that phone, which would've also confirmed whether the phone was used to set-up crimes or not.

It was all a ruse to get their precedent for backdoors, and now they're dripping this (probably bullshit) story to the media in a way that further progresses their agenda, after classifying the information in the first place.