`titrebSUMMARY`/titreb `!-- 495:'RESUME' --bFieldwork in a major juvenile court in the Paris area shows how the use of strict incarceration criteria considerably reduces the possibility for taking into account a young offender’s personality and past. The decision to incarcerate, by getting rid of the youth, soon becomes the grounds on which magistrates and public prosecutors make a stand that expresses their own identity. Behind official motivations are rationales of a relational sort that lead prosecutors and magistrates to defend current positions and identities. When deciding whether or not to incarcerate a minor, judges use their sense of what is right and just toward the adolescent in light of his offense ; but they do so by referring to a sense of identity whereby they position themselves within their occupational corps. As a consequence, the person who counts is not so much the juvenile offender as the magistrate who decides his fate. This does not comply with the key principle of the Ordinance of 1945, which instituted juvenile justice and recommends that, above all, the minor’s personality be taken under consideration.