Politics and policy are centrally implicated in the socio-historical construction of youth justice responses, yet the contexts, mechanisms, and processes influencing the ‘making’ of youth justice policy remain under-researched and poorly understood. The limited research evidence base devoted to youth justice policy-making (YJPM) has tended towards reductionist conceptualisations of ‘policy’ as restricted, static outcomes produced by governmental policy ‘actors’. However, privileging the YJPM status and role of senior governmental policy actors serves to reify their claims to being the ‘expert’ youth justice knowledge holders. This legitimises their exercise of power and ‘governance’ over non-governmental groups (e.g., civil servants, frontline practitioners, and academics) by dominating knowledge creation and claims to expertise in policy-making contexts. This research, therefore, seeks to identify and elaborate these complex, relational, and dynamic contexts and the attendant mechanisms of change that interact to drive YJPM. Semi-structured interviews with different stakeholder groups across youth justice contexts identified distal (macro) and proximal (meso/micro) contexts—mechanism relationships that drive YJPM. We conclude that the dynamic influence of organisational and professional identity (i.e., self-identity and identity assigned to others) is significant across contextualised mechanisms of YJPM, particularly the perceived identity, status, and role of the expert who attributes the credentials to contribute effectively to policy-making processes. This, in turn, leads us to discern and discuss three distinct characterisations of the youth justice policy–evidence–expertise nexus, namely: (i) evidence-endorsed policy; (ii) evidence-based policy; and (iii) evidence-enhanced policy.

Reviews of youth justice intervention effectiveness prioritise hierarchies of evidence that obscure how contextual features shape the 'mechanisms' of change in preventative interventions. This article critiques this current evidence-based approach to youth justice interventions and its reliance on reoffending reduction as a measure of effectiveness. Community-based prevention programmes have been central to youth justice, since the late 20th century in England and Wales. However, by concentrating primarily on effect sizes, this approach often overlooks the influence specific contexts have on the mechanisms that can facilitate behaviour or attitude change through these preventative interventions. The authors propose that a realist approach could enhance understanding by focusing on how interventions work, for whom, and why. The article begins by outlining key theories that underpin youth justice programmes, followed by an overview of the realist synthesis (RS) approach to evidence review. This approach emphasises the mechanisms behind interventions and the contextual factors influencing their success. The authors apply this perspective to two types of community-based interventions used with two distinct and different groups of children: Intensive Supervision and Surveillance and Restorative Justice Conferencing in Referral Orders. The study makes three contributions. First, it provides an original detailed account of conducting an RS in the youth justice context, demonstrating the value of realist methods in evaluating youth justice interventions. Second, it highlights that youth justice interventions are often underpinned by competing programme theories that, in practice, work both in harmony and tension - producing a more diverse set of outcomes beyond simple proclamations of interventions being effective or not. Third, it emphasises that understanding and refining these underlying theories can improve children's outcomes in youth justice programmes through practical guidance.

Collaboration with justice-involved children is a central tenet of the 'Child First' guiding principle for the Youth Justice System of England and Wales. However, exactly what constitutes 'collaboration' is moot in policy, practice and research with vulnerable children in contact with support systems, and currently neglected within youth justice contexts. As we discuss, children's collaboration is typically modelled and operationalised in adult-centric, static ways, based on levels of involvement and how professionals can facilitate children's (often inequitable) participation in planning and decision-making. This article utilises data from justice-involved children who participated in the 'Child First Collaboration Project' via a Project Reference Group (n = 22) and system journey interviews facilitated by creative methodologies conducted with children across a range of youth justice stages (n = 66). Analyses identified a dynamic and relational 'cycle of collaboration' containing four inter-related mechanisms: asking, listening to, respecting and informing children, throughout processes within and beyond the Youth Justice System. Where this cycle and its mechanisms were enacted, children perceived child-centric, effective, authentic collaboration. Where they were not (or not fully), children perceived adult-centric, ineffective, disingenuous 'collaboration' more akin to tokenistic consultation. Therefore, it is recommended that the Child First 'collaboration with children' tenet and associated practice guidance be augmented to reflect this evidence-based and dynamic 'cycle of collaboration'.

Children are extremely vulnerable yet often treated as adults, measured by adult-centric conceptualisations of 'guilt' and expected to decide on their own culpability for law infringement. In addition, system agents incentivise children to admit guilt by offering contingent support or implying further consequences for refusal, resulting in a youth justice system that exacerbates this by requiring admissions of guilt throughout the process. We explore difficulties of applying adult-centric understandings of 'guilt' to children through our typology of guilt, which examines responses children might give to questions of guilt and asks whether applying adult-centric notions of guilt erodes 'Child First' youth justice.

Youth justice policy making has been conceptualised as a reductionist, linear and decontextualised process dominated by governmental actors producing static policy ‘products’. However, semi-structured interviews with a range of expert policy actors illuminated youth justice policy-making (YJPM) as a complex, dynamic social construction shaped through relationships across professional contexts. Analyses discerned coherence from chaos in YJPM contexts characterised by simultaneous stability-change, conflict-ambivalence, short-termism and precarity. YJPM contexts were constructed and experienced by experts working in governmental and non-governmental contexts as the relational and dynamic features shaping the mechanisms through which policies are made and operate over time at multiple different levels of the social system.

Chapter 4 examines youth justice policy development from 2010 (post-Labour government) under the Coalition and then Conservative governments during a period shaped by significant socio-economic austerity and socio-political insecurities that rendered the expansionist 'new youth justice' approach to prevention increasingly infeasible – financially, politically, practically and evidentially. It argues that socio-economic austerity and socio-political insecurity have exerted a reconstructive influence on youth justice policy making since 2010 by motivating a more pragmatic retraction and retrenchment of policy and practice, supported by the reimagining of alternative, evidence-based, principled youth justice approaches. The chapter charts the evolution of youth justice policy since 2010, from a consolidated, rebranded 'new youth justice' into a more explicit strategic focus on integrating progressive 'Child First' principles to meet prevention goals. It concludes by asserting that the '3Es' of expansionist youth justice policy, be they 'effectiveness, efficiency and economy' (Home Office, 1998) or 'expedience, evidence and experience' (Smith, 2014), have been tentatively replaced by the '3Ps' of austerity youth justice: politics (change), pragmatism (necessity, rationality) and principle (Child First).

Policy development and implementation has a pivotal role in the youth justice system, profoundly impacting professionals and the children they work with. This imaginative book challenges limited explanations of policy-making as linear and government-dominated through original research into the practices, identities and relationships of a wide range of stakeholders working in multiple policy- making contexts in England and Wales. The result is a detailed expert analysis of the contexts and mechanisms of youth justice policy-making. This book is key reading for researchers, professionals and students seeking effective understandings and responses to the long term social problem of youth offending.

Policy development and implementation has a pivotal role in the youth justice system, profoundly impacting professionals and the children they work with. This imaginative book challenges limited explanations of policy-making as linear and government-dominated through original research into the practices, identities and relationships of a wide range of stakeholders working in multiple policy- making contexts in England and Wales. The result is a detailed expert analysis of the contexts and mechanisms of youth justice policy-making. This book is key reading for researchers, professionals and students seeking effective understandings and responses to the long term social problem of youth offending.

This chapter explores the nature and extent of the revolutionary youth justice reforms under the Labour government and the ideas that influenced them (1997–2010). This socio-historical period is presented as being underpinned by an expansionist approach to youth justice, with large amounts of money, resources and time invested into sweeping policy reform, mobilised by the construction of a plethora of youth justice systems, structures, laws, sentences, strategies and practices. The chapter begins by tracing the emergence of Labour's radically new youth justice policies, strategies and practices. It outlines the recommendations from the Audit Commission's 'Misspent youth' review of youth justice in the United Kingdom (1996) and the subsequent 'No more excuses' government White Paper (1997), which formalised a set of strategies that coalesced to form the 'new youth justice'. There follows a detailed discussion of the radical reconstruction of youth justice through the Crime and Disorder Act 1998, most notably the creation of the Youth Justice System of England and Wales, with its central aim/policy of prevention. The chapter concludes with an investigation of youth justice developments in the two years following the first decade of 'new youth justice' under Labour (2008–10), evaluating the extent to which these developments evidenced an extension of and progression from 'new youth justice'.

Policy development and implementation has a pivotal role in the youth justice system, profoundly impacting professionals and the children they work with. This imaginative book challenges limited explanations of policy-making as linear and government-dominated through original research into the practices, identities and relationships of a wide range of stakeholders working in multiple policy- making contexts in England and Wales. The result is a detailed expert analysis of the contexts and mechanisms of youth justice policy-making. This book is key reading for researchers, professionals and students seeking effective understandings and responses to the long term social problem of youth offending.

Policy development and implementation has a pivotal role in the youth justice system, profoundly impacting professionals and the children they work with. This imaginative book challenges limited explanations of policy-making as linear and government-dominated through original research into the practices, identities and relationships of a wide range of stakeholders working in multiple policy- making contexts in England and Wales. The result is a detailed expert analysis of the contexts and mechanisms of youth justice policy-making. This book is key reading for researchers, professionals and students seeking effective understandings and responses to the long term social problem of youth offending.

Policy development and implementation has a pivotal role in the youth justice system, profoundly impacting professionals and the children they work with. This imaginative book challenges limited explanations of policy-making as linear and government-dominated through original research into the practices, identities and relationships of a wide range of stakeholders working in multiple policy- making contexts in England and Wales. The result is a detailed expert analysis of the contexts and mechanisms of youth justice policy-making. This book is key reading for researchers, professionals and students seeking effective understandings and responses to the long term social problem of youth offending.

Policy development and implementation has a pivotal role in the youth justice system, profoundly impacting professionals and the children they work with. This imaginative book challenges limited explanations of policy-making as linear and government-dominated through original research into the practices, identities and relationships of a wide range of stakeholders working in multiple policy- making contexts in England and Wales. The result is a detailed expert analysis of the contexts and mechanisms of youth justice policy-making. This book is key reading for researchers, professionals and students seeking effective understandings and responses to the long term social problem of youth offending.

Policy development and implementation has a pivotal role in the youth justice system, profoundly impacting professionals and the children they work with. This imaginative book challenges limited explanations of policy-making as linear and government-dominated through original research into the practices, identities and relationships of a wide range of stakeholders working in multiple policy- making contexts in England and Wales. The result is a detailed expert analysis of the contexts and mechanisms of youth justice policy-making. This book is key reading for researchers, professionals and students seeking effective understandings and responses to the long term social problem of youth offending.

Policy development and implementation has a pivotal role in the youth justice system, profoundly impacting professionals and the children they work with. This imaginative book challenges limited explanations of policy-making as linear and government-dominated through original research into the practices, identities and relationships of a wide range of stakeholders working in multiple policy- making contexts in England and Wales. The result is a detailed expert analysis of the contexts and mechanisms of youth justice policy-making. This book is key reading for researchers, professionals and students seeking effective understandings and responses to the long term social problem of youth offending.