I'm not sure what point this little blurb is making.
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in a nutshell.  Crimes that leave little (if any) physical evidence and have no witnesses are difficult to obtain convictions.  It has always been thus .... and always will unless the state decides to use it's power to overrule the rights of the accused.
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Maybe the G&M could come up with some suggested solutions rather than reporting old news ad nauseam.   Ideally one that doesn't prejudice the right to fair treatment before the courts.