This isn't "tracking", this is attribution in a court. The defence can't stand there and say "That's not him/this device" when the forensics point exactly at it.
To be fair, the courts in USA apparently have a different definition of tracking than all normal people do. Speaking of car movements, Flock claims this isn't tracking people based on some legalese mumbojumbo. Obviously, this and GPs claims are absolutely ridiculous if you speak English, but are apparently true in american legalese doublespeak.