1Expertise has played an essential role in the historical construction of juvenile violence as a social problem. Violence as an intimate and social phenomenon often associated with youth is understood in both objective and subjective terms. Its importance can be measured by its multiple expressions in the public sphere. The expert, who is situated at the centre and periphery of the child protection system, gathers this expression and gives it form. Thus youth violence is often filtered, interpreted, and circulated by expert discourses.

2Experts became interested in this question of violence very early on. As of the 18^th century, forensics supported justice in seeking to identify the bodily traces1. From bodily scars to wounds in the soul, from the 1820’s on, psychiatry shifted the ground of investigation as well as the expert’s position, replacing an indicial servitude in addressing judges with an authoritative discourse on criminal madness2. Then, in the 20^th century, expertise diversified, reflecting the proliferation of scientific disciplines given over to the heuristics of the human being. It contributed to a more complex definition of violence, ranging from the visible to the invisible: from physical to psychic violence, and even to symbolic violence. Experts moved beyond making simple diagnoses and entered the field of treatment of violence, joining others in the practice of care and rehabilitation. This regeneration of the violent or victimized child also involves the normalization of bodies and behaviours, where child protection and social defense work hand in hand.

3This expertise on violence – an avatar of rationalizing modernity – gradually organised the realm of ‘the social’ in the 19^th century, especially the judicial system, which led it to a dominant position in the child protection field. Physicians, psychiatrists, psychologists, pedagogues, sociologists and anthropologists have addressed the question of youth at risk, helping to define a target population for public policies. This very early interest paid to the childhood domain should undoubtedly be seen in connection with the primordial role which childhood has played in the generalization of psychiatry, from the moment when, as Foucault explains, it became “the filter for analyzing behaviour” (even adults’ behaviours):

[...] it seems to me that it is by taking childhood as the target of its action, both of its knowledge and its power, that psychiatry succeeds in being generalized. That is to say, childhood seems to me to be one of the historical conditions of the generalization of psychiatric knowledge and power3.

4Expertise emanates from social and professional practice, based on what experts claim is scientific knowledge. Its intervention is threefold: the identification and recognition of a singular phenomenon, a classificatory and etiological will, and a therapeutic and prophylactic proposal that guides decisions of institutions. While making claims to scientific objectivity, experts may have effectively stigmatized and constructed social problems. Indeed, experts have proceeded in a paradoxical manner in establishing their legitimacy: while they exaggerate the complexity of studied objects through a sometimes abstruse nosography, they also contribute to the vernacular of ‘common sense’, reproducing stereotyped figures, subtly organizing science and doxa, technocratic authority and legitimization through public opinion. Media exposure plays a major role both in the dissemination of scientific knowledge and in this duality: “The details are the property of experts, but the general structure is remarkably common knowledge4”, explains Ian Hacking, for whom

[...] knowledge, or at any rate what is experienced as knowledge at some time, is of two kinds that shade into each other? There is expert knowledge, the knowledge of the professionals, and there is popular knowledge that is shared by a significant part of the interested population. Some expert knowledge is always esoteric, but in the more flagrant cases of making up people, the expert quickly becomes exoteric5.

5This expert knowledge is constituted as an instrument of power, even if it remains subjected to other forms of authority (notably justice). It functions, as Michel Foucault has shown, by gathering information on a given population, and then in restituting this knowledge in the form of a power which it imposes on these populations. This analytical and classificatory practice is the consequence of a will to social regulation which acts discreetly. Consequently, its action on the social body appears to be a consequence of classification, whereas it may actually be the cause. Thus, following Pierre Bourdieu, one might suggest that this operation of expertise involves symbolic violence, a process whose efficiency lies in the fact that the actors are not aware of the constraints weighing on them, having incorporated the discourse of expertise into their own identity. This knowledge and, in its secularised form, expertise, are effective communication channels in this process of incorporation of dominant representations, as they are able to naturalise social constructions and their classifications6. Hence we must consider both the violence reified by the expertise and the violence exerted by the action of expertise. Yet the historiography of the past twenty years has shown how these classificatory processes encounter the actors’ agency, causing attempts at resistance, subversion or avoidance and, despite the unequal distribution of the symbolic capital, always constituting sites for negotiation in the elaboration of norms. Thus Ian Hacking insists on the dynamic interactions between classifications and the individuals or behaviours they apply to, through what he calls the looping effect: classifications affect the people classified, and these affects in turn change the classifications7.

Classifications can change our evaluations of our personal worth, of the moral kind of person that we are. Sometimes this means that people passively accept what experts say about them, and see themselves in that light. But feedback can direct itself in many ways. We well know the rebellions of the sorted. A classification imposed from above is rearranged by the people to whom it was supposed to apply8.

6In this framework, experts appear among the five key players in the looping effects and making up people (a-classification, b-people, c-institutions, d-knowledge, e-experts):

Finally there are (e) the experts or professionals who generate or legitimate the knowledge (d), judge its validity, and use it in their practice. They work within (c) institutions that guarantee their legitimacy, authenticity, and status as experts. They study, try to help, or advise on the control of the (b) people who are (a) classified as of a given kind9.

7Expertise is intrinsically linked to the liberal regulation of the societies which emerged in the 18^th century and was brought to fruition in the 19^th century. Unlike the sovereign’s discretionary and inquisitorial power, expertise confers a new form of authority on the liberal government, resulting from knowledge claiming its objectivity, producing a discourse of truth about humanity (about individuals as well as populations)10. Liberalism established knowledge of societies as a necessity, and as a condition for the very exercise of governing them11. This erudite authority renders possible and, simultaneously, justifies the installation of a “conduct of conducts”, according to Michel Foucault12. It is not a question of regulating the functioning of societies by the rule of law, but of forming a norm which applies to individuals and social groups, in integrating their characteristics, their experience and their subjectivity into it. As a form of power that is that much more efficient in being economical, the liberal government takes over the infra-political sphere so as to engender the social body through knowledge of it, a circularity of knowledge and power. The family is its favoured territory, the object of increasing and various interventions under the leadership of experts13. Youth is a social object it contributes to fabricating, in the power that youth holds for engendering ‘the social’, while the future is replacing the past in the founding reason of societies.

8Experts occupy a strategic position between the State and the social body: their scientific observations enable them to inform as well as to apply public policies. The crisis of the liberal State at the end of the 19^th century reinforced their power. Noting the inaptitude of the market to regulate societies, multiple social security programmes were enabled. Experts are the privileged actors in these programmes, in charge of governing society through the social, that is in mobilizing the resources of social actors for more readily gaining their assent and increasing the effectiveness of the power thus exerted on these populations. Hygenism, education, family relationships, sexuality, work, health: related apparatuses fill up the social biography of individuals, and politicize the private sphere by making it a terrain of intervention, but in de-politizing certain social struggles in socializing them via the principle of “solidarism”14. If the intervention became more intense, the mobilisation of the recipients of the social policies is also greater. For example, at the beginning of the 20^th century, juvenile justice became a focal point of coordination for a myriad of interventions with specific rationalities, incarnated by a multitude of experts targeting the child at risk, all the while making the family a strategic site of acculturation to the dominant cultural values of the liberal society: competency, autonomy and responsibility. All the same, this normalising power of expertise does not exclude the maintenance of a disciplinary power, for the expert categorizes homogenizes and hierarchizes, and, in so doing, traces a line of demarcation between the normal and the pathological15.

9On the theoretical level, several transversal questions deserve to be raised:

10Expertise functions as a competency linked to a specialisation, notably involving the technocratisation of public policies. But it also draws its legitimacy from its externality: in importing exogenic knowledge into a given field, it intends to confer distance and objectivity. Tensions exist between competency and externality; can we try to develop an ecology of expertise? The exogenic dimension of expertise entails the production of a discourse of truth: where a constituted rationality struggles to establish truth, a cross-checking of expert skills, completes, confirms or rectifies the initial diagnosis. There where a professional body produces and reproduces judgments specific to its social field, expertise brings the detachment and confrontation of praxes, sometimes at the risk of assuming a competitor position16. However, we might also argue that this exogeneity results from a mixing of heterogeneous rationalities, a source of confusions and errors in evaluation. The practice of expertise is not very reflexive, and it frequently introduces an epistemological hiatus between various disciplines. The case of law is exemplary as to confusions of competencies: where juridical logic identifies causes and effects in the development of proofs, psychiatry delves into medical epistemology (epidemiology, symptomatology) and embraces factors leading to the advancement of diagnostic hypotheses, exposing judges to the risk of constituting a causal proof out of a simple correlation or a simple symptom. Thus, by its epistemological “externality”, not only does expertise not inevitably contribute to a cross-checking and a consolidation of the initial opinion, but amounts to a potential source of error or compromise in the judgment. Finally, beyond these epistemological ruptures, there remains an implicit ethics of judicial expertise: isn’t truth supposed to produce what is just? Far from being a guarantee of objectivity, the externality revendicated by the expertise involves a strangeness and epistemic curiosity which is crossbred with the “grotesque”, to take a point from Foucault17.

11Is the expert a moral entrepreneur? If morals and truth have long been synonymous, the laicization of knowledge has theoretically divided these two concepts. Yet don't morals persist in fertilizing expert knowledge, particularly in the field of youth protection? Thus, in her analysis of the Canadian moral reform movement, Mariana Valverde highlights the porosity of these two paradigms: “one characteristic of moral/social reform discourse was that the dichotomies of theory vs. practice, science vs. charity, were eliminated in favour of a holistic image of a knowledge that would be simultaneously scientific and charitable, true and useful18”. Along these same lines, philanthropy and science are described as “neither antagonistic nor mutually exclusive categories. Private moral and social reformers, therefore, often pioneered modern relief methods and made important contributions to social research [...]19”. Although they didn’t always practice them all that easily, many actors from moral regulation movements have at the very least borrowed the forms of an apparent scientific rigour, producing new experts, authorizing the current historiography to establish “significant lines of filiation between the emergent social sciences and moral regulation activism20”.

12Expertise has moreover contributed to forging a new discourse on risk and its management through governmental processes, making the expert’s image that much more ambiguous. The depository of a knowledge founded on an examination of facts, the expert is summoned to render a prospective analysis, capable of unraveling an uncertain future21. Risk technologies have at once consolidated the expert’s power and undermined his/her knowledge. “With risk policies”, explains François Ewald, “everything takes place as if power had given up on the idea that a good policy had to be the reflection of a scientific assignment of causalities […] the idea of causes has been abandoned for that of factors -multiple, varied, disseminated, risk variables; we pass from the idea of causality to one of statistical correlation22”.

13Faced with this indeterminacy, is the expert a savant working on objective facts, or an oracle, whose predictive function, and, by the same token, his/her speculative function, has become primordial? What is more, Ulrich Beck underlines that “the social effect of risk definitions is [...] not dependent on their scientific validity23”. Also, in the risk society, the privilege of a science become expert knowledge, which was to function internally in erecting a cult of doubt, only to convert that doubt into dogma in the policy field, has crumbled, leaving expert knowledge at grips with common sense knowledge24. Far from being an appeal for a restoration of the opacity of expert power, in the manner of Ivan Illich, Beck’s influential text invites us to transform this mutation into a resource for liberating people from the supervision of experts without, for all that, renouncing science, or even expertise25.

14Expertise, having made a major entry onto the scene of law and justice, presents features apparently contradictory with a law conceived as constitutive of a public space fostering the exercise of citizenship, for it functions on a technocratic mode and presents itself as a non-deliberative authority. Consequently, is expertise compatible with liberal law? Additionally, as Danièle Bourcier and Monique de Bonis ask, “what is the relationship between ‘accuracy’ and ‘justice’? How are we to relate the expert’s word, who must speak of facts, and the judge’s, who speaks of law?26”. In more than one way, the junctions and tensions between expert, scientific and judicial truths deserve attention. That much more so in view of certain more immediate functions surrounding the expertise of judges. Indeed, as regards child welfare, the “protectional” label revendicated by legislations and systems set up at the turn of the 20^th century plays a strongly disculpabilizing role. And, furthermore, should we not ask ourselves whether recourse to expertise doesn’t further reinforce this function? In bringing its soothing virtues to he/she who mobilizes it, the expert becomes a veritable anxiolytic for the judge confronted with the anguishes of judging27. These soothing virtues were described by Foucault, who extended their power to all the actors involved:

[...] consider the cowardly relief of judge, jury, journalists, spectators, etc., when a psychiatrist or psychologist tells them not to be afraid to find a defendant guilty, that they will not be punishing the offender, but merely providing for his/her rehabilitation and cure. The defendant is found guilty, sentenced, imprisoned. The court is acquitted.28

15We need to open other pathways, and set out the thematic projects needed for compiling this history of expertise, which this work’s authors have contributed to illustrating. For, if we need to envisage the expert in the great theater of governmentality, he/she must also be depicted in the dense and specific environment of the institutions, populations and (micro) power apparatuses within which he acts.

16What is the history of the circulation of models of expertise on the national and international scales? If the first experts entered the scene within the philanthropical networks of the 19^th century, the professionalization of the resulting organizations took place rapidly, with the holding of international congresses by the end of the 20^th century, and recognition of expertise in the century by international organizations in their infancy (the International Labour Organization initially, then the League of Nations, and, principally, the United Nations)29. These authorities played a determining role in the recognition and functioning of expertise. The expertise language became the hegemonic idiom of these transnational organizations. What cultural transfers did they allow, and what national resistances did they give rise to?

17Several contributions in this work are dedicated to expertise in professions dealing with youth at risk. It is important to reveal the identity of these experts, their professional training and the networks they form, according to a prosopographical procedure. For mutual-recognition founds recognition within an expertise organized in a market which fosters competition but also allows the superposition of expertises. Consequently, we will look into the factors that have allowed the rise in mastery of a discipline to the rank of expert knowledge, legitimizing the intervention of its representatives in the decision-making process. Does a codified deontology exist, specific to each field of intervention, which can thwart conflicts of interest?

18The institutions of expertise, also receive the authors’ special attention. The role of institutions taking responsibility (reformatories, orphanages and medical­pedagogical institutions, etc) is essential in fostering expert knowledge. In their specialization, they have favoured these expert practices. One consequence is that expertise has contributed to relegitimising the practice of confinement, decried in the early 20^th century, while certain institutions have been able to instrumentalise expertise in attracting new populations on the rehabilitation market.

19What do we know about these populations subjected to expertise, as well as those requesting it, since, taking as an example what Foucault remarks in relation to psychiatric evaluation, it should be kept in mind that this idea of expertise can be requested and not just imposed30? Do there exist recurring profiles, depending on the age group, gender, ethnic origin, social class, etc? Their positions when faced with a discourse of expertise should be described: between acceptance and rejection, instrumentalisation and submission31, mistrust and credulity.

20A good part of the expertise concerning youth at risk is mobilized by juvenile courts. How do expertise and justice function during the various stages of judicial intervention: the role of expertise in the establishment of the evidence, in diagnosis, in prognosis, and in recommending judicial treatment? The various experts intervening in a juvenile court should reconcile their interests. Do they function in symbiosis or in conflict, depending on the reciprocal forms of instrumentalisation? And lastly, what is the impact of expertise in the area of judicial intervention? Childhood, as a generic paradigm of human behaviour, as a period of life to be protected, has permitted justice to extend its prerogatives.

21What about the knowledge constituting expertise? If the expert’s legitimacy depends on the knowledge he/she relies on, a good part of his activity remains marked by empiricism. These skills, attained from within their field of activity may present tautological biases, with the populations observed already being stigmatized. More generally, the effect of looping between knowledge and power produces scientific impasses. Moreover, the nosographical complexity of the expertise often gives way to a standardisation in the etiologies and recommendations for treatment. What is the compatibility of the various expertises mobilized, for example, between the socio-genesis of youth violence and the psychologisation of approaches? If we sometimes witness their hybridization, there are frequent cases where rationalities are superimposed whereas in fact they mutually refute one another.

22What is to be said, finally, about expertise in the public sphere? When expertise and media discourses cross paths, can we affirm that the experts take part in the manufacturing of opinion or that they are manipulated by media oracles? Inevitably, there exists a political role for expertise, which consequently abandons its position of scientific withdrawal to the advantage of public intervention32.