Source : Free On-Line Dictionary of Computing

net.police
     
        /net-p*-lees'/ (Or "net police", "net.cops") Those {Usenet}
        readers who feel it is their responsibility to pounce on and
        {flame} any posting which they regard as offensive or in
        violation of their understanding of {netiquette}.  Generally
        used sarcastically or pejoratively.
     
        See also {net.-}, {code police}.
     
        [{Jargon File}]