> In that case, it's illegal to look in the phone book for names starting with "john" because that's not a specific user.
No. Working with that analogy, this ruling indicates you can't get one warrant that applies to everyone in the book - simply because they are listed in the same geographic area.
A phone-book warrant would not be in harmony with the 4th Amendment.
Does it mean that it would be constitutional if each tower kept its own log? Or then, if the database server collated a separate log for each tower as it went?
How would one-log-per-tower be different from a surveillance video tape?
Hmmm... elements of an answer: there is no doubt more in the decision but from the EFF writeup: (1) "individuals have a reasonable expectation of privacy in the location data", (2) "sensitive information about a person’s associations and allow police to “follow” them into private spaces", (3) "require a provider, almost always Google, to search “the entirety” of its reserve of location data “while law enforcement officials have no idea who they are looking for, or whether the search will even turn up a result.”"
So it sounds like one-log-per-tower would take care of the third point (the warrant would call for 1-4 specific towers or something), but the court still found an expectation of privacy in cell phone location, and an expectation that this sensitive private info might intrude of private spaces. As opposed to a video camera which views a public space.
No. Working with that analogy, this ruling indicates you can't get one warrant that applies to everyone in the book - simply because they are listed in the same geographic area.
A phone-book warrant would not be in harmony with the 4th Amendment.