While the total number of under-18s in custody in England and Wales has fallen dramatically since 2010, the proportion of black, Asian and minority ethnic (BAME) young people who are detained is rising - recently topping 50 per cent for the first time.
In May, there were 415 BAME young people in young offenders institutions and secure training centres, and 396 white young people, according to Ministry of Justice (MoJ) figures (see graphic). This rate is disproportionately higher than the population as a whole - 20 per cent of under-18s are non-white.
In its strategic plan 2019-22, the Youth Justice Board (YJB) describes disproportionality as a "critical concern" among its priorities, and the document admits that "children may not be receiving equal treatment due to their ethnicity".
The rise comes two years after Labour MP David Lammy published his review on overrepresentation of BAME offenders in the criminal justice system and recommendations for reducing this.
Given the broad support for Lammy's findings across the youth justice sector, the news has prompted accusations that the government and justice agencies are not doing enough in response.
Following the latest figures, the MP for Tottenham tweeted: "Since my review, disproportionately has gotten worse. These figures put Britain among the very worst in the world. Young lives are being blighted, while the public picks up the tab for prison places and serial unemployment. We need urgent, rapid and sustained intervention."
What is going wrong?
A number of themes have been identified as potentially playing a part in disproportionality, from an unconscious or more overt racial bias across the judicial system - including the use of police stop-and-search powers and variable quality of legal advice - to distrust of the police and poverty-related vulnerability to crime.
Most agree there is no single feature to blame, and that ongoing work is required to understand all the issues and address them.
Questions have also been raised as to whether there has been an appropriate response to Lammy's key challenge to "explain or reform".
The report stated: "If criminal justice agencies cannot provide an evidence-based explanation for apparent disparities between ethnic groups, then reforms should be introduced to address those disparities."
"Sufficient explanations have not been forthcoming and reform is evidently lacking," says Pippa Goodfellow, director of the Standing Committee for Youth Justice.
Penelope Gibbs, director of charity Transform Justice, adds: "No one really knows why the disproportionality exists as no good research has been done, but is likely to be linked to harsher enforcement and punishment on knife crime.
"The answer is to do some good research as to how children of different ethnicities are treated by the court system.
"Where is the MoJ's evidence base for why custody is so disproportionate, and where is the plan to meet the issues thrown up by that evidence?"
Goodfellow warns that the introduction of knife crime prevention orders, due to come into force later this year, risk further exacerbating racial disparity in child custody levels. The orders, which can be used to control at risk behaviour, could lead to the criminalisation of children aged 12 upwards.
"The introduction of these orders is likely to damage already strained relations and trust between BAME communities and the police," says Goodfellow, adding: "Given the current race disproportionality that exists across several aspects of the criminal justice system, it is likely that BAME children and young people will be particularly affected, as the orders can be imposed on the basis of subjective tests.
"With the public and political spotlight focused on ‘serious youth violence', it is crucial that policies designed to tackle these issues don't exacerbate differential outcomes for BAME children."
What is being done?
The MoJ claims to have accepted all 35 recommendations in the Lammy review, and to be taking them forward in some way.
It particularly highlights it has been "reviewing fairness of sentence outcomes and working to improve black, Asian and ethnic minority children's trust of legal advice", as well as improving parental understanding and engagement.
It says it is working with other government departments and the YJB to understand the links between disproportionality that occur before children enter the system, including in education, as well as disproportionate arrest and caution rates.
The Magistrates Association and Youth Custody Service are being engaged to "explain or change", and the Judicial Office has also launched unconscious bias training for magistrates and legal advisers which began in June.
The YJB will use its Journey of the Child model to highlight disproportionality at key points in a young person's path through the system, and there may be annual reporting of each agency's response.
Another recommendation of Lammy's review was that the YJB publishes a full evaluation of its "disproportionality toolkit" trial, and identify potential actions (see case study).
The board says that data is being collected this year and refined to help create a best practice toolkit in 2020, which will then be available for local authorities to use.
The YJB is also in the process of identifying two local authorities to act as "pathfinders" on good practice, focusing on the courts and the early entry into the system through the police.
Other areas the plan seeks to influence are employability and sport as a means of "building on the strengths of black children to help them to desist from harmful behaviour".
Colin Allars, chief executive of the YJB, says: "We know that the changes needed are complex, but we are determined to play our part."
Buckinghamshire: YJB toolkit raises staff awareness
Buckinghamshire Youth Offending Service has been using the YJB Summary Ethnic Disproportionality Toolkit, as well as internal data collection and analysis, to research the issue locally.
It found that children from BAME backgrounds were overrepresented in the youth justice system, more likely to enter the youth justice system at a higher level, and more likely to receive stiffer sentences, including custodial.
All staff have received unconscious bias training and secured commitment from courts that magistrates will complete the training.
A pilot scheme has been launched to remove names and ethnicities from a pre-court triage process and a working group set up to understand local causes, linking in with a Race Disparity Audit by Thames Valley police. It is due to complete in September, followed by further analysis. It has also committed to address ethnic disproportionality to all pre-sentence reports.