The Black Fleet of Sto-Vo-Kor

[Nightfall]

The ID you purchased (or any ID for that matter) has nothing to do with the tag you carry (the yellow-flashing faction on your reputation window - hit F8 to see, scroll to the bottom).
In order to loose the Police tag, go kill every lawful NPC in Rheinland (though, I think you have the Liberty Police tag so I suggest you fly to Bonn Station and kill the Interspace Commerce depots there). Watch your reputation all the time, you may also want to kill Hessians to get a Corsair tag.

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If the stars should appear one night in a thousand years, how would men believe and adore and preserve for many generations the remembrance of the city of God? - from 'Nightfall' by I. Asimov
The Outcasts consider Siniestre Nube a sacred place for several reasons. Early explorers discovered a jumphole within the depths of the cloud that leads to a strange world of ringed stars and strange craft. All ships in the burrial ground are placed facing that hole to honor the Alien Spirits. - An Outcast rumor