The current framework, published in 2013, features 10 standards in a 50-page document, but under proposals put out to consultation by the Youth Justice Board, these will be condensed into four standards, plus an additional new one, in a document currently 25 pages long.
John Drew, who is also senior associate at the Prison Reform Trust, said the decision to simplify and broaden the framework risked losing lessons learned, and decisions becoming more subjective.
The draft document sets out national standards for youth justice services to be used by youth offending teams and other professionals working with children in the justice system.
These standards cover broad areas: "out of court", "at court", "in the community", "in secure settings" and "on transition" - a new standard reflecting the transitions children and young people can experience in the community and the secure estate.
This is in comparison with standards in the current document with more detailed titles, such as "preventing offending", "bail and remand management" and "planning and delivering interventions in the community".
Drew described the draft standards as a "radical departure" with potential risks.
"I don't think these are national standards," he said.
"They are something much looser than that. I fear they are too loose and they haven't got as strong a basis as they could have, while still being much looser, in important lessons that have been learned over the years.
"There are bound to be some things in the previous national standards that are really, really important," he continued.
"When you no longer specify them, but you have a much more broader and permissive framework, which is what they [the YJB] are trying to do, then you're relying on people interpreting much looser phrases in the way that you wish."
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One example he pointed to was the way a local authority should respond when a child in care is in custody. He said current guidelines should ideally have been rewritten with more detail, to ensure a child's entitlements are clear.
However, the looser wording in the document would leave professionals to "decide what to do according to their local situation".
Drew also pointed out that the simplified document is at odds with frameworks produced by youth justice inspectorates, including Ofsted, HMI Prisons and HM Inspectorate of Probation, which could lead to confusion among professionals.
"Is the YJB, in some sense, giving up its responsibility to set national standards and leaving it in some way to the inspectorate?" he said.
The consultation paper published alongside the draft standards states that the revised standards are intended to "reflect the maturity of the youth justice system; the YJB's move to outcome-focused oversight; rationalise them into a condensed set of functions; and, move away from process-driven requirements".
It also states that the guidelines are based on the YJB's "child first, offender second" principle and "aim to prioritise the best interests of children in the youth justice system, promote their strengths and capacities, encourage their active participation and promote crime-free lives."
The new standards are set to come into force from April 2019. The consultation is open until 26 November.
