Because police are unnecessary. That is: there is no socially valuable service¹ which police provide which also necessitates the existence of a professional privileged class of goons with an absolute and unquestioned authority to murder whomever whenever. I'm not saying that police are unnecessary in the sense that there are bad actors and that it isn't socially necessary for there to be some structure in place to protect individuals of a society against these bad actors. I am speaking specifically against that structure existing as a profession. ¹I mean in a general mutual aid social-utility sense; the obvious and unspoken "valuable service" the police provide is the protection of the capitalist class and the enforcement of their property rights.