The Court of Appeal recently passed judgment in long-running private children proceedings brought under the Children Act concerning arrangements for two children to spend time with their father following allegations against him of aggressive behaviour.

In this article, Jenny Bowden discusses the recent decision of Mr Justice Cusworth, reported as A & B (Children: expert’s reports). This decision reminds us of two key points: the high threshold when appealing case management decisions and the test of “necessity” when granting permission for expert evidence.



The separated mother and father had been unable to agree appropriate arrangements for the two children, now aged 11 and 7, to spend time with their father and, as a result, court proceedings had been issued.

There had been several hearings over a prolonged period, including two fact-finding hearings to determine allegations against the father raised by the mother. These resulted in findings that the father had behaved in “ways that were controlling, manipulative and aggressive towards the mother”. The court noted that the mother “was not always beyond criticism” herself but did not make any findings about alienating behaviours, which the father had alleged were factors in the impasse. Despite the involvement of various professionals with the family (including a guardian appointed for the children), the children were spending no time with their father.

In February 2023, the children’s guardian applied for the appointment of a psychologist to assess the parents and suggested that the psychologist consider whether an assessment of the children would also be beneficial. That application was rejected.

In December 2023, the father applied for the appointment of a psychologist with a slightly different scope: he sought a family assessment of both parents, with the psychologist also seeing the children, if appropriate. While effectively seeking the same relief as the children’s guardian, his application was made after further attempts to rebuild his relationship with the children had failed (and after he had engaged in domestic violence programmes).

The guardian supported the application, which was heard by the same judge who, less than a year earlier, had declined to permit the appointment.

The judge granted the father’s application and ordered the appointment of a psychologist, selecting the guardian’s preferred expert.

The mother appealed, and it is that appeal that is discussed here.


The law

The court has the power (and indeed a duty) to control what evidence is provided. Rule 25 of the Family Procedure Rules (FPR) and the associated practice directions set out clear guidance on the involvement of experts.

Either party can make an application seeking expert evidence where it appears specialist information is needed, which the court will then consider. Expert evidence is preferred from a single expert (jointly instructed by the parties), and common examples are experts advising on drug or alcohol testing/analysis, family therapy, psychological assessment or reports from social workers.

The provisions of the FPR should be considered alongside section 13 of the Children and Families Act 2014, which governs expert evidence in children proceedings. The court’s permission is required, and the court should only grant that permission “if the court is of the opinion that the expert evidence is necessary to assist the court to resolve the proceedings justly” (s13(6)).

There have been numerous cases in which the threshold of “necessity” has been explored.


The appeal decision

As noted above, the first instance judge granted permission for a psychologist to be instructed. The mother was not happy with that decision and appealed. Mr Justice Cusworth considered the case and allowed the appeal despite the high threshold for appealing case management decisions. He felt the first instance judge had failed to identify any proper basis upon which the appointment of a psychologist could be considered necessary in the present proceedings.

While many other avenues had failed to restore the relationship between the children and the father, the court at first instance had effectively instructed the expert to “generally” assess both parents and possibly the children “in the hope that something might turn up to unlock the problem”. This wasn’t appropriate. The judge referred to the test of necessity, considering the judgment in Re AV [2020] and the 2021 memorandum from the President of the Family Division, which records: “Such expert evidence will only be ‘necessary’ where it is demanded by the contested issues rather than being merely reasonable, desirable or of assistance. This requirement sets a higher threshold than the standard of ‘assisting the court’.”

The judge also felt that the scope of the instruction had not been properly considered or determined, so there was no clarity as to what the expert should be providing evidence on. This procedural flaw only emphasised the difficulty in deeming the instruction necessary. The judge said: “The fact that other avenues have failed to produce a positive outcome cannot of it itself render the obtaining of such evidence necessary, without the identification of certain issues about which expert evidence is required.”



This case is a reminder of the high (but not insurmountable) bar when seeking to appeal a case management decision. Appeal judges should be reticent to interfere with directions provided by a judge at the first instance, who ought to have greater visibility of the issues, scrutinise all applications for expert input and carefully consider how best to shepherd the case to a conclusion. Appeal judges often do not have the same insight as the judges dealing with multiple hearings between the same parties. In this case, Mr Justice Cusworth felt the first instance judge erred in failing to articulate why the psychological assessment was necessary.

Partner Toby Atkinson comments on this judgment: “The court will not appoint an expert simply to find a solution when an impasse exists, absent a cogent application articulating why their involvement is necessary and how their evidence will assist the court. Those seeking to instruct experts in children proceedings should consider carefully the rationale for the instruction and make clear to the court why the instruction is necessary.”



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