I worked in that field for some time; my background was in management in finance so it was considered to give me credibility for life skills counselling, especially with regard to employment and social interactions. Our inmates were closely monitored, but those allowed off premises during the day were required to hold jobs and to pay board, and to participate in household chores just as they would in a family. Most were short-termers by the time we got them. We may have shown a handful a better way to deal with life, in a more conventional way, but truthfully it's impossible to evaluate what impact we may have had on a larger scale. Perhaps five years or so down the road someone may have realized that what we tried to tell them was right and ultimately worked for them. Many didn't return to the system while I was there; others came through again and again, but not through our program. Among the younger guys I think that the greatest influence that turned them around to a more law-abiding approach was time and maturity. At a certain age they began to develop a greater sense of self and of the personal consequences of their actions, and decided that they wanted more from life than they'd created for themselves. Then the non-crime life was more attractive and more rewarding.
Again, it was hard to evaluate our impact overall because a large proportion of our population was classed as forensic (psychiatric) in one way or another. That doesn't mean that most or even many actually went for the NGIR defense: it wouldn't have worked for most in any event.