Actually, I don't think either shame or guilt is a primary factor in Restorative Justice. It is true that one can see shame as penitence in offenders who have gone through a successful intervention. Nevertheless, when the conferencing process works, something quite else is going on.
First of all, as I've shown, we must learn to identify all four expressions of shame: withdrawal (which is the kind of shame most people love to see because it makes them believe that the one who blushes wants to return to the herd); attack self (a way of currying favor with others in order to remain protected); avoidance (all the ways we try to make the physiological affect and all its associated memories go away); and attack other (a way of reducing the self esteem of others in order to at least feel better than someone.) To say that shame is expressed only when withdrawal behavior appears is like trying to explain the nature of highway traffic when you recognize only one brand of automobile as a possible part of that traffic. Drug use, masochism, most "impulsive" violent action, joy rides, and a host of other behavior classified as criminal form a significant part of the general response to shame and must be recognized as such if we are to change society.
What, then, is going on in a conference aimed at restoring a community that has been injured by action that is defined as criminal? Most importantly, I believe, the members of that community are brought together and allowed to express their feelings about the incident. It was a wise society that removed most disputes from unmodulated public "discussion" in order to maintain useful order. As all of us know, over the centuries during which the legal system evolved, it became a theater within which lawyers and judges became the protagonists, while victims and perpetrators were increasingly marginalized. The large and growing fraction of punished offenders who continue to act against their community despite what was intended as "correctional" imprisonment is taken by most of us as an indication that the current system is in need of repair.
What, then, is a community? As I have indicated in the article "Crime and Nourishment: When the Tried and True become the Tired and False," (available on the Tomkins Institute Website elsewhere on Behavior OnLine), a community is a collection of public interpersonal relationships within which we attempt to mutualize and maximize positive affect, mutualize and minimize negative affect, to express as much affect to each other as possible, and to foster there three goals with as much power as possible. The current criminal justice sytem interferes with nearly all aspects of these rules for community formation.
The conference system, as developed by the Australian policeman Terry O'Connell, codified by his colleague John MacDonald, and explicated by their colleague David Moore, flies directly in the face of this historical trend and obeys all of the principles articulated above and in the article mentioned. Routinely, those who work in the way articulated by O'Connell (and now taught throughout the US and Canada by Ted Wachtel's RealJustice program) note that only when the disparate forces jockeying for position and attacking each other and vying for attention and living in what the physicist calls Brownian motion begin to obey the rules so mentioned does community begin to appear, and only after this neocommunity formation does the offender realize that s/he is outside the community. It is this recognition, that "I" am shorn from the herd, which brings awareness of shame to the offender, who then "minds" the experience of shame because now that there is a community worth belonging to, expulsion or exile from it really hurts.
This is true restorative justice because it not only restores the ofender to the community but it rebuilds and reinforces and recreates the community during its process. It is about justice because it really does deal with matters of right and wrong, of morality and our sense of what it means to be a human in a world of other equally valued humans.
Many believe that the "correct" treatment of offenders is to make them feel shame, and that they must therefore provide methods redolent of the stocks in Williamsburg or denunciation in church or various forms of exile. Yet although such management techniques work for people who are already securely linked to their community, they are terribly ineffective for the great mass of offenders who are already marginalized and poorly connected to others.
There is no such thing as reintegrative shaming. There is only reintegration, only hard work aimed at the reinforcement of community and the hope that the offender finds the community enough of a source of positive affect that return to it is worth a huge dose of shame as withdrawal. I view as cruel and eventually counterproductive all attempts to humiliate those who have committed crimes against their community unless those offenders are clearly and evidently linked securely to that community.
There is enough shame already available in our shared world. No one needs to produce more. Needed badly is better understanding of the relation between community cohesion and shame, between those who live comfortably within the community and those already full of shame and so marginalized, between those who think that shame is a verb and those who understand that community is an energy-consuming process.