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Oxford based Paediatric Neurosurgery Expert Witness Services
What Judges say of our experts
From HHJ H.'s Staffordshire vs XXX judgement, 17.07.2020
I found Mr. Calisto to be an excellent expert witness. Again, he was not in any way dogmatic. He demonstrated clear professional curiosity and is clearly authoritative in his field. His evidence was appropriately cautious. He recognised the limits of what science can and cannot tell us and he was very open and willing to consider the range of alternative scenarios and possibilities which were put to him. He was also willing and alive to the possibility of an unknown cause.
However, despite extensive cross-examination and exploration, he remained clear and firm in his ultimate conclusions.
Central Bedfordshire Council vs F & Ors [2022] High Court Judge
Mr Calisto is a Consultant Paediatric Neurosurgeon from the John Radcliffe Hospital in Oxford, and an honorary senior clinical lecturer at Oxford University. He continues a long tradition of excellence in this field from that hospital. I had not heard him give evidence before. He originally deferred giving evidence because he was unwell, and came back later to assist the Court when he had recovered. His contribution was worth waiting for.
Mr Calisto was a most impressive witness. It struck me several times during the course of his examination and cross-examination that he combined those rare qualities of a high degree of clinical experience, excellence and learning with an appropriately open mind. He is very obviously able, discussing each aspect and the foundation of either clinical experience and/or learning, and was able to contrast and comment on the two. For example only, in considering the blood in the spinal column, Mr Calisto said that it was not possible to say whether it was caused by a direct bleeding or had tracked down, but he was able to discuss (in-depth) the strength and weaknesses of the arguments for and against. For example, Mr Calisto was able to bring in the Choudhary paper, which had been relied on by Dr X. They were all good examples of the considerable persuasive force and strength of Mr Calisto's evidence, and just how they applied to this case. It was impressive and I rely on it. He brought to this case a depth and intelligence which is invaluable.
Family Court at Wolverhampton, September 2025.
Dr C., Dr H. and Mr Calisto were, in the view of the Court, impressive and persuasive witnesses. Their mastery of their respective fields of expertise was to be expected given their experience but their ability to explain the difficult medical concepts at play in the case was nothing short of excellent. All three experts were ready to accept that which they did not know and to consider the views of the other experts. They all demonstrated an openness to the views of the other experts and a willingness to reconsider their own views. The evidence of Dr C., Dr H. and Mr Calisto – both individually and collectively; played a pivotal role in the change of position of the Local Authority and the decision of the Court to sanction the application to withdraw the proceedings in respect of child X and child Y.
HHJ L.