In reference to a married or co-habitating couple, on parole refers to when one's spouse or partner is out of town, leaving the other person to temporarily live a pseudo-single life style, wasting time and money in an orgy of short-lived freedom. Often characterized by the person hanging out with his or her single friends, that have probably not been contacted in a long time. Also refered to as a jail break.
Dude, Sally is out of town. So John is on parole! He wants us to hit up the titty-bars every night this week!