Katt asks below if Foucault uses the term “self-policing” in his work.
Sometimes when I have a question like this I use books.google.com to search (they have digitized many though not all Foucault books). In this case you will not find that phrase (or “self-police,” or either of those without the hyphen).
But need we just be limited by that phrase? The idea is prominent enough in Foucault (a related term is “conduct of conduct” which refers to the conduct of others and oneself,) and receives a lot of attention in his “technology of the self and others” phase of his work toward the end of his life; that is, the “governmentality” phase.
These ideas are nicely summarized in the piece known as “The Subject and Power” which forms an afterword to Rabinow and Dreyfus’ book Michel Foucault Beyond Structuralism and Hermeneutics (1983). For example, see pp. 220-1.
The Security, Territory, Population series of lectures coming out this week also discuss “conduct” a lot.
I think we know also that Foucault’s use of the term “police” refers to the historical usage of it, which was originally much wider than its current meaning, and was related to governance. And therefore could indeed include “self-policing.”
So there is plenty of discussion of this idea in Foucault (another one is the great interview, actually a favorite of mine “Ethics of the concern for the self as a technology of freedom.”)