Abstract. Warsaw, a metropolis of commonwealth and Duchy of Warsaw, had an independent police government system from the rest of administration. Special organs and special military units secured the public safety, law and order very well. In reality, the biggest authorities in the field of security and police, in Duchy of Warsaw, were given to a Mayor of Warsaw. The article analyses Self – dependent police government of Warsaw project. This specific document was a work of the Police Minister Aleksander Potocki. He proposed intensification of police government in Warsaw and finally led to the creation of a self – dependent structure of police in the whole country. Unfortunately the plan was not realized because the costs were too high. Moreover, the project did not ensure the the qualitative improve of the police work. Self – dependent police government of Warsaw project did not pass, but played a very important role in future reforms of polish administration.