Law enforcement is not a part of the working class. Law enforcement actually represents a very distinct class that does not fall easily into the capitalist/worker paradigm.
They are guaranteed economic security, due to state privilege, state employment, police unions and pensions. They are also given special legal status that gives them privilege in respect to acting violently.
They don't own the means of production. They do, however, own the means of enforcement on claims of capital. That is a product or service that they have a full monopoly on. And they use it primarily to protect the elite, the state and the individuals at the top of the hierarchy.