@WestminsterPup ... any investigation is unlikely to lead to a prosecution or "a positive outcome"
Other issues:
Technology: an example - GPS isn't 100% accurate. Some are not hackable
Protocols: Police must follow strict guidelines in law. Sometimes, decisions are made by third parties.
@WestminsterPup Context:
First and foremost, an investigation depends on the support of a victim (with some exceptions).
The main evidential lines of enquiry are: witnesses, forensics, and CCTV images.
If none are available, then...
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