After the revolution, most of the states disbanded their militias, but New Jersey did not. Their militia served as a sort of state police, unless they got called up. At least this is what I learned from doing genealogical searches. Each town was expected to appoint or elect a representative to the militia, who doubly served as sheriff and militia member and was paid by the town.
No they did not disband their militias. Where the hell did you get that falsehood. The Militia Act of 1792 was law of the land until the 1860s, and the current militia laws (10 USC 311) bears many similarities to the original act.