The Upper Tribunal has rejected the Home Office’s argument that special weight should be afforded to age assessments carried out by the National Age Assessment Board (NAAB), reaffirming that the same settled principles, including the benefit of the doubt owed to an applicant, apply regardless of which body conducts the assessment.
Following a fact-finding hearing, Upper Tribunal Judge Bruce accepted the age given by BSB, an Eritrean national whose case had been delegated to the NAAB by the London Borough of Hillingdon. Read the judgment here.
Background
BSB claimed to have arrived in the UK when he was 16 years old. He has since been accepted as a refugee and a victim of trafficking, and diagnosed with post-traumatic stress disorder.
Prior to coming to the UK, BSB had made various attempts to enter the UK from Dunkerque. He provided different names and details during encounters with the authorities which ultimately became a feature of this case.
On arrival in the UK, BSB gave his date of birth as 14 April 2007, making him 16 years old. UK Border Force also carried out a preliminary age assessment, finding that he was 28 years old and born in 1996 (a staggering ten years older). This assessment was based entirely on his physical appearance and demeanour.
BSB was therefore assessed as an adult and accommodated in a hotel. A month later, social workers from the London Borough of Hillingdon carried out their own brief enquiry into age. On 10 May 2024, they found he was likely to be between 22 and 25 years old. This assessment was based on credibility as well as his appearance. This decision was challenged via the pre-action protocol and later withdrawn. He was then accommodated as a child by Hillingdon.
In October 2024, his case was referred to the NAAB. The NAAB social workers found that he was between the ages of 19-22, with a final date of birth of 14 February 2005. This date of birth was taken from the first date that he had given to British border control in Dunkerque.
The case was relatively unusual in that there was a mere two years between the age given by BSB and the age that he was ultimately assessed as. BSB did not have any documents to prove his age.
Judicial review proceedings were issued challenging the NAAB assessment. Permission was granted and BSB was returned to local authority care. The case was then transferred to the Upper Tribunal for a fact-finding hearing.
How age assessments are conducted
The Home Office introduced the NAAB under the Nationality and Borders Act 2022 (see sections 49 to 57 of the Act). The aim was to maintain greater control over asylum age assessments as well as to ‘improve consistency, expertise and quality’.
The NAAB does not replace a local authority’s jurisdiction to conduct an age assessment; it works alongside a local authority. A local authority can refer a case to the NAAB if it believes that the assessment is particularly complex, and if the referral is accepted, the child will be assessed by NAAB social workers instead. It remains a decision for the local authority as to whether to refer into the NAAB, but it will be bound by its outcome.
While the NAAB should allow for appeals against age assessments, it is not possible yet. At this stage, judicial review remains the only method to challenge an age assessment.
NAAB social workers must follow the same legal approach as local authority social workers as set out in the determination.
Click here to read the principles to be applied in age assessments which were summarised in R (AB) v Kent County Council [2020] EWHC 109 (Admin).
Purpose of the assessment
(1) The purpose of an age assessment is to establish the chronological age of a young person.
Burden of proof and benefit of the doubt
(2) There should be no predisposition, divorced from the information and evidence available to the local authority, to assume that an applicant is an adult, or conversely that he is a child.
(3) The decision needs to be based on particular facts concerning the particular person and is made on the balance of probabilities.
(4) There is no burden of proof imposed on the applicant to prove his or her age.
(5) The benefit of any doubt is always given to the unaccompanied asylum-seeking child since it is recognised that age assessment is not a scientific process.
Physical appearance and demeanour
(6) The decision maker cannot determine age solely on the basis of the appearance of the applicant, except in clear cases.
(7) Physical appearance is a notoriously unreliable basis for assessment of chronological age.
(8) Demeanour can also be notoriously unreliable and by itself constitutes only ‘somewhat fragile material’. Demeanour will generally need to be viewed together with other things including inconsistencies in his account of how the applicant knew his/her age.
(9) The finding that little weight can be attached to physical appearance applies even more so to photographs which are not three-dimensional and where the appearance of the subject can be significantly affected by how photographs are lit, the type of the exposure, the quality of the camera and other factors, not least including the clothing a person wears.
Conduct of the assessment
(10) The assessment must be done by two social workers who should be properly trained and experienced.
(11) The applicant should be told the purpose of the assessment.
(12) An interpreter must be provided if necessary.
(13) The applicant should have an appropriate adult, and should be informed of the right to have one, with the purpose of having an appropriate adult also being explained to the applicant.
(14) The approach of the assessors must involve trying to establish a rapport with the applicant and any questioning, while recognising the possibility of coaching, should be by means of open-ended and not leading questions. Assessors should be aware of the customs and practices and any particular difficulties faced by the applicant in his home society.
(15) The interview must seek to obtain the general background of the applicant including his family circumstances and history, educational background and his activities during the previous few years.
(16) An assessment of the applicant’s credibility must be made if there is reason to doubt his/her statement as to his/her age.
(17) The applicant should be given the opportunity to explain any inconsistencies in his/her account or anything which is likely to result in adverse credibility findings.
Preliminary decision
(18) An applicant should be given a fair and proper opportunity, at a stage when a possible adverse decision is no more than provisional, to deal with important points adverse to his age case which may weigh against him. It is not sufficient that the interviewing social workers withdraw to consider their decision, and then return to present the applicant with their conclusions without first giving him the opportunity to deal with the adverse points.
The decision and reasons
(19) In coming to the conclusion the local authority must have adequate information to make a decision independent of the Home Office’s decision.
(20) Adequate reasons must be given.
(21) The interview must be written up promptly.
The local authority retains responsibility for safeguarding, accommodation and any looked-after child duties; it just doesn’t make the final decision on age.
As per R (on the application of NXP and NAN) v Secretary of State for the Home Department (Age assessments: venue – respondent) [2026] UKUT 192 NAAB judicial reviews follow the same transfer directions as claims against a local authority. Claims are issued in the Administrative Court and transferred to the Upper Tribunal after a decision on permission. The respondent will be the Home Secretary and a local authority should be included in the claim as an interested party, as they will be responsible for accommodating the child should their claim be successful.
Should special weight be attached to assessments carried out by the NAAB?
The NAAB jurisdiction is relatively new. Within the few judgments that have arisen, the Home Office has attempted to argue that special weight should be attached to assessments carried out by the NAAB, relying on the statutory framework that created it. In the case of SS handed down in December 2025, UTJ Hirst did not consider it appropriate in a fact-finding hearing to give general guidance as to the weight to be attached to a NAAB age assessment and considered that each case must be assessed on its own merits.
In BSB, the Home Office again sought to argue that a ‘greater degree of deference’ should be given to a NAAB assessment, because the scheme was national and the higher level of training meant that the decisions were likely to be more consistent and of higher quality than those produced by the various local authorities.
This argument was firmly rejected by UTJ Bruce on several grounds. No authority supported it. It would also unfairly disparage highly trained, experienced social workers who were not employed by the NAAB (it was noted that one of BSB’s assessors was previously employed by a local authority and there was nothing to support that he had become a better social worker on joining the NAAB). Further, no evidence had been provided that NAAB social workers receive better training, and in any case, NAAB social workers were bound by the exact same legal authority and policy as those working for local authorities.
What weight should be attached to the age assessment?
Both NAAB age assessors were suitably qualified professionals with appropriate expertise and the age assessment was both an ‘impressively detailed piece of work’ and generally Merton-compliant. Nonetheless, UTJ Bruce levelled a number of criticisms as to their overall conclusions.
First, the age assessors relied on facts that were inaccurate and misleading. They wrongly stated that BSB had given five different names and dates of birth in Dunkerque, and wrongly recorded that he had denied being in Dunkerque when he had in fact admitted to it. UTJ Bruce found it ‘quite wrong’ to say BSB had given five different dates of birth, and incorrect to suggest that BSB had hidden the truth about Dunkerque.
Second, the age assessors produced two identical witness statements that set out their reasons for finding that BSB was not the age that he claimed to be. Despite stating in their assessment that little weight had been at attached to appearance and demeanour, the witness statements demonstrated that they had placed a fairly significant amount of weight on what they considered to be physical markers of adulthood. This was found to be inconsistent.
Moreover, the markers relied on by the age assessors were simply incorrect. For example, BSB did not have eye wrinkles and deep lines on his forehead, and it was ‘entirely possible for boys as young as 15 to have fully established facial hair’. In fact, he had taken pride in his beard growth, ‘proudly’ sporting a healthy beard at the hearing.
The judge also found that there were significant shortcomings in the conclusions on BSB’s demeanour. BSB was described as polite, cooperative and sincere. However, no credit was awarded to him for his genuine attempts to be helpful during a difficult and stressful process with the age assessors being quick to find that he was attempting to mislead.
The assessors also failed to acknowledge that he had been accepted by the Home Office as a refugee and a victim of trafficking. They focused on peripheral details and minor inconsistencies instead of looking at the bigger picture, including that his account had remained consistent throughout his numerous dealings with the local authority and the Home Office.
It was therefore concluded that only limited weight could be attached to the age assessment.
Summary
UTJ Bruce acknowledged that BSB had not told the truth about everything, including the nature of his eventual arrival to the UK and the fact that he had given different dates of birth. However, his claim for international protection and to be a victim of trafficking was genuine and while migrants are often pressured to give certain stories concealing methods of entry, the account he had given was detailed and complex and had been tested during interviews and cross-examination.
It was concluded that BSB was the age that he claimed to be on the balance of probabilities. The case is a useful reminder of where the balance of probabilities lies in age assessments as well as a confirmation that social workers – even if they have prepared a detailed piece of work – are fallible.
Perhaps most importantly, the case confirms that NAAB age assessments should be litigated in the same way as those against the local authority. Any attempts by Home Office to suggest that special weight should be attached to their own age assessments should be strongly rebuffed.