Hi, Axille:

Interesting question. Normally, supervisors-compared with subordinates-perceive more procedural justice and perceive the mediation as more effective. Moreover, subordinates' perceptions of mediation effectiveness are determined by perceptions of procedural justice: especially when confronted with low levels of procedural justice, their perceptions of mediation effectiveness are negatively affected. This is not true for supervisors! Please take a look at the following recent research study great references:

In this article, the authors (Bollen, Ittner, & C. Euwema, 2012) examined the relationship between an employer's implementation of a typical dispute resolution system (DRS) and organizational justice, perceived compliance with the law, and organizational commitment. They draw on unique data from a single, geographically expansive, U.S. firm with more than 100,000 employees in more than 1,000 locations. Holding all time- constant, location-level variables in place, they find that the introduction of a DRS is associated with elevated perceptions of interactional justice but diminished perceptions of procedural justice. They also find no discernible effect on organizational commitment, but a significant boost to perceived legal compliance by the company. The authors draw on these findings to offer a "differential- effects" model for conceptualizing the relationship among organizational justice, perceived legal compliance, and the implementation of dispute resolution mechanisms.

• Bollen, K., Ittner, H., & C. Euwema, M. (2012). Mediating Hierarchical Labor Conflicts: Procedural Justice Makes a Difference-for Subordinates. Group Decision & Negotiation, 21(5), 621-636.

Hope this helps!

Nadeem

Hi  Axille Sobry: The study of the papers mentioned may perhaps give the requite ides. regards.

• Alexander, S. and Ruderman, M. (1987), “The Role of Procedural and Distributive Justice in Organizational Behavior”, Social Justice Research, Vol. 1, No. 2, pp. 177-197.

• Aryee, S., Budhwar, P.S. and Chen, Z.X. (2002), “Trust as a Mediator of the Relationship Between Organizational Justice and Work Outcomes: Test of a Social Exchange Model”, Journal of Organizational Behavior, Vol. 23 No. 3, pp. 267-85.

• Beth, L., Brent, A.S., Cindy, P.Z. and Jason, A.C. (2009), “Procedural Justice, Interactional Justice and Task Performance: The Mediating Role of Intrinsic Motivation”, Organizational Behavior and Human Decision Processes, Vol. 108, No. 1, pp. 93-105.

• Bies, R.J. and Moag, J.S. (1986), “Interactional Justice: Communication Criteria of Fairness”, Social Justice Research, Vol. 1, No. 2, pp. 199-218.

• Cathleen, L.M., Philip, H.S. and Alan, R. (2011), “Auditor and Non-mentor Supervisor Relationships Effects of Mentoring and Organizational Justice”, Managerial Auditing Journal, Vol. 26, No. 1, pp. 5-31.

• Chiaburu, S.D. and Lim, S.A. (2008), “Manager Trustworthiness or Interactional Justice? Predicting Organizational Citizenship Behavior”, Journal of Business Ethics, Vol. 83,

pp. 453-476.

• Cohen-Charash, Y. and Spector, P.E. (2001), “The Role of Justice in Organizations: A Meta-Analysis”, Organizational Behavior and Human Decision Process, Vol. 86, No. 2,

pp. 278-321.

• Colquitt, J.A., Conlon, D.E., Wesson, M.J., Porter, C.O. and Ng, K.Y. (2001), “Justice at the Millennium: A Meta-analytic Review of 25 Years of Organizational Justice Research”, Journal of Applied Psychology, Vol. 86, No. 3, pp. 424-445.

• Folger, R. (1991), “Distributive and Procedural Justice: Combined Impact of Voice and Improvement on Experienced Inequality”, Journal of Personality and Social Psychology, Vol. 35, pp. 108-119.

• Greenberg, J. and Tyler, R.T. (1987), “Why Procedural Justice in Organizations?”, Social Justice Research, Vol. 1, No. 2, pp. 127-142.

• Masterson, S.S., Goldman, B.M., Lewis, K. and Taylor, M.S. (2000), “Integrating Justice and Social Exchange: The Differing Effects of Fair Procedures and Treatment on Work Relationships”, Academy of Management Journal, Vol. 43, pp. 738-748.

• Niehoff, P.B. and Moorman, H.R. (1993), “Justice as a Mediator of the Relationship between Methods of Monitoring and Organizational Citizenship Behavior”, Academy of Management Journal, Vol. 36, No. 3, pp. 527-556.

• Viswesvaran, C. and Ones, D.S. (2002), “Examining the Construct of Organizational Justice: A Meta-Analytic Evaluation of Relations with Work Attitudes and Behaviors”, Journal of Business Ethics, Vol. 38, No. 3, pp. 193-203.

Maybe you can use GAVRIELIDES, T., “Restorative Justice Theory and Practice: Addressing the Discrepancy”. European Institute for Crime Prevention and Control, Afiliado con las Naciones Unidas, Helsinki Finlandia, 2007

Hi Axelle.  Some of the following might be of help.