It is rare for the court to reject “expert” evidence placed before it on the grounds that it is not expert evidence at all. This is rarer still now that permission is normally required before expert evidence can be adduced.  It is worthwhile for all litigators (and experts) to read the decision of Mostyn J in GM v Carmarthenshire County Council & Anor [2018] EWFC 36.  It is a family case, however the principles relating to the nature  and utility of expert evidence are universal.  The principles relating to the nature of expert evidence are encapsulated.



The applicant mother was applying for the discharge of a care order made over her child.


The local authority, opposing the mother’s application, obtained permission to rely on an expert report from an independent social worker.


    1. The guardian and the local authority placed great weight on evidence from an independent social worker, Cathy Webley, about L’s “attachment profile”. This evidence was authorised by an order of the court on 29 January 2017. In making that order the court must have been satisfied that the evidence was “necessary” to assist the court to resolve the proceedings (see section 13(6) of the Children and Families Act 2014). In Re TG (a child)[2013] EWCA Civ 5 at para 30 the President stated:
“The test of what is “necessary” sets a hurdle which is on any view significantly higher than the old test of what is “reasonably required“”.
    1. With the greatest respect, I have concluded that this evidence does not satisfy the new test. Indeed, in my judgment, it does not even satisfy the old one.
    2. In Barings Plc v Coopers & Lybrand [2001] PNLR 22, at para 45, Evans-Lombe J held:
“In my judgment the authorities which I have cited above establish the following propositions: expert evidence is admissible under section 3 of the Civil Evidence Act 1972 in any case where the Court accepts that there exists a recognised expertise governed by recognised standards and rules of conduct capable of influencing the Court’s decision on any of the issues which it has to decide and the witness to be called satisfies the Court that he has a sufficient familiarity with and knowledge of the expertise in question to render his opinion potentially of value in resolving any of those issues.”
    1. This was approved by Hildyard J in the RBS Rights Issue Litigation [2015] EWHC 3433 (Ch) at paras 13 – 14. At para 17 he continued:
“In determining whether particular evidence is reasonably required a key question will be:
“…whether the subject matter of the opinion is such that a person without instruction or experience in the area of knowledge or human experience would be able to form a sound judgment on the matter without the assistance of witnesses possessing special knowledge or experience in the area.”
See R v Bonython (1984) 38 SASR 45 at 46, cited in JP Morgan Chase v Springwell [2006] EWHC 2755 (Comm) at [20] and Barings at [38].”
    1. Thus, in order to be admissible in civil proceedings the expert evidence must be:
i) contained within a recognised body of expertise governed by recognised standards and rules of conduct relevant to the question which the Court has to decide; and
ii) of such a nature that that a person without instruction or experience in the area of knowledge or human experience would not be able to form a sound judgment on the matter without the assistance of a witness possessing special knowledge or experience in the area.
    1. This is the test for admissibility in civil proceedings. As explained above, the test in family proceedings is significantly higher.
    2. In her report dated 23 March 2017 at page 5 Cathy Webley stated:
Theoretical Framework
This assessment is based on attachment theory. Attachment refers to the specific dynamic relationship that develops between an infant and their primary carer. During the first year or two of life children develop certain attachment patterns in response to the quality of caregiving they receive. Babies whose needs are met consistently and sensitively will normally develop secure patterns of attachment. Within sound attachment relationships children learn about basic trust that will serve as a template for future emotional relationships. Children with secure attachments learn to regulate their emotions and control their behaviour. With the parents providing a secure base, the child is free to explore and learn. Eventually, a child can hold the symbolic representations of attachment figures inside then to feel secure even without the physical presence of the caregiver.
With less optimal caregiving, the child has to adapt and try to organise a strategy to keep the pound close and engaged. This organisation of an adaptive strategy does not mean that the child fails to form an attachment. However, such strategies come at a price and may lead to a variety of problems as the child grows and develops.
If an infant’s expressions of need are routinely rejected or dismissed, the child will learn to shut down feelings of dependency, a style of attachment known as avoidant. In later adolescent (sic, semble adolescence) and adulthood this pattern of minimising the importance of feelings and relationships is referred to as dismissing.
If on the other hand the caregiver responds to the infant’s demands but in an unpredictable way the child may develop a strategy of escalating attachment-related behaviours by becoming more clinging and demanding, while at the same time their anxiety makes them resist being comforted. This pattern of attachment is known as ambivalent. In later adolescence and adulthood it is referred to as preoccupied or enmeshed.
The children are exposed to frightening behaviour from their caregiver, they may be unable to organise a strategy at all, as their drive to look to their caregiver for care and protection results in fear and increase, rather than decrease, in anxiety. This style of attachment is known as disorganised. Such children can develop highly controlling behaviours as they grow older but this masks underlying vulnerability and distress. In late adolescence and adulthood, this pattern is referred to as unresolved and is linked to the development of personality disorders.
Attachment patterns established in infancy are resistant to change once this early developmental stages pass, even if the caregiving environment changes, but over time, with reparative parenting, and, in later life, supportive relationships, new more secure patterns of attachments can begin to override existing patterns.”
    1. A number of points may be made about this description of the theory. First, the theory, which I suppose is an aspect of psychology, is not stated in the report to be the subject of any specific recognised body of expertise governed by recognised standards and rules of conduct. Indeed, I asked the advocate for the guardian whether he was aware whether a student could undertake a degree in attachment theory, or otherwise study it at university or professionally. Mr Hussell was not able to answer my question. Therefore, it does not satisfy the first criterion for admissibility as expert evidence.
    2. Second, the theory is only a theory. It might be regarded as a statement of the obvious, namely that primate infants develop attachments to familiar caregivers as a result of evolutionary pressures, since attachment behaviour would facilitate the infant’s survival in the face of dangers such as predation or exposure to the elements. Certainly, this was the view of John Bowlby, the psychologist, psychiatrist, and psychoanalyst and originator of the theory in the 1960s. It might be thought to be obvious that the better the quality of the care given by the primary caregiver the better the chance of the recipient of that care forming stable relationships later in life. However, it must also be recognised that some people who have received highly abusive care in childhood have developed into completely well-adjusted adults. Further, the central premise of the theory – that quality attachments depend on quality care from a primary caregiver – begins to fall down when you consider that plenty of children are brought up collectively (whether in a boarding school, a kibbutz or a village in Africa) and yet develop into perfectly normal and well-adjusted adults.
    3. For my part I would say with all due respect that I do not need a social worker to give me evidence based on this theory to help me form a judgment about L’s attachments.
    4. In her executive summary Cathy Webley says:
“On balance, I feel that the risks to L of a return home at this stage are too high and that he should have the opportunity to consolidate the evident progress he is making in his settled foster placement. My conclusion may have been different if L’s foster placement was unsuitable or was in danger of disrupting. However that is not the case. L is happy, settled on making secure attachments in the way that his care plan was designed to achieve. L is more resilient than he was but he remains more vulnerable than most children. I would be concerned about disrupting him again and moving him into an uncertain future with his mother.”
This opinion is based on supposed expert evidence, but it seems to me to be no more than a standard welfare officer recommendation, and one that does not place any weight at all on the principle of proportionality, or on the right to respect for family life, as explained by me above, let alone on the positive duty of the local authority to take measures to achieve a reunification of the blood family. Indeed, it is noteworthy that on page 15 of her report the very first matter relied on by the independent social worker against the mother’s case is in these terms:
“L has been told he will be staying long-term with [the foster parents] and has made an emotional investment in his new family. He would undoubtedly find separation for his foster family, whom he has learnt to love and trust, distressing, even if he appeared outwardly happy.”
If L has been told that he will in effect be staying permanently with his foster parents then that would be a major dereliction from the positive duty imposed on the local authority to seek to take measures to reunify this family. I cannot see how this factor can be relied on first and foremost by the independent social worker.
  1. I cannot say that this so-called expert evidence has assisted me in reaching the decision I must make.
  2. In my judgment, in any future case where it is proposed that expert evidence of this nature is adduced I would expect the court to determine the application with the utmost rigour, and with the terms of this judgment at the forefront of its mind.”