Policy paper

Nationality and Borders Bill: safeguarding through age assessment

Updated 13 October 2023

1. What are we going to do?

The UK typically receives over 3,000 asylum claims from unaccompanied asylum seeking children (UASC) per year. However, between 2016-2021 there were 6,177 cases where age was disputed and subsequently resolved, of which 58% were found to be adults.

In one instance pupils raised alarm at an obviously mature adult joining their class. He was re-assessed to be 10 years older than his claimed age. 

Between 2016-2020, 71% of UASC were recorded as being 16 or 17 years old. The graph below, (which shows all asylum applications, not just UASC applications), reveals an unexpected spike in the number of people claiming to be 16 and to a lesser extent, 17. There is a marked drop in applications from those claiming to be 18 and over.

Source: Subset of data published in Asy_D01, Immigration Statistics, Home Office

There are clear safeguarding issues which arise if a child is inadvertently treated as an adult, and equally if an adult is wrongly accepted as a child and placed in accommodation with younger children to whom they could present a risk.

There are currently incentives for adults to claim to be under 18 years old. Unaccompanied children generally receive a greater level of support than adults in several respects, including the accommodation they are provided with, the procedural and substantive treatment of their asylum claims, the arrangements that would need to be made to secure their possible removal and the circumstances in which they can be held in immigration detention.

Our reforms aim to make assessments more consistent and robust from the outset, with any disputed decisions resolved quickly and conclusively. We will create a power to enable the Home Secretary to introduce secondary legislation specifying scientific techniques of age assessment, which would widen the breadth of evidence on which to base decisions.

2. How are we going to do it?

The Government has brought forward proposals to mitigate against the risk that adults will be placed alongside children, and to ensure vulnerable children can swiftly access appropriate support.

When an individual does not have any definitive documentary evidence to support their claimed age, and if there is doubt over their claim to be a child, there is a need to assess their age.

Local authorities can carry out what is known as a ‘Merton’ compliant age assessment. A Merton age assessment is a holistic, social worker-led assessment which must adhere to standards that have been set out by the courts in several judgments dating back to 2003. As a result, the requirements and standards expected from a Merton assessment are not set out in a single place. Therefore, we will aim to bring more clarity to the process by setting out in Regulations a uniform set of standards, adherence to which would be mandatory, in order to achieve greater consistency in age assessments.

We will also establish a decision-making function in the Home Office, referred to as the National Age Assessment Board (NAAB). The NAAB will primarily consist of expert social workers whose task will be to conduct full age assessments, upon referral from a local authority. Local authorities will also retain the ability to conduct age assessments themselves.

Given the very difficult task of assessing someone’s age, we will also consider introducing scientific age assessment methods to widen the evidence available to decision-makers and improve the accuracy of their decisions. Where the Home Secretary specifies a scientific method or methods in subsequent secondary legislation, the Bill will allow a decision-maker to be able to take a negative credibility inference from a refusal to undertake that scientific assessment, without good reason. The UK is one of the only countries in Europe not to use scientific age assessment methods to help determine a person’s age when they arrive in the country. Various scientific methods are used to assess age in, among others, Sweden, Norway, Finland, France, Germany and the Netherlands.

Currently, where someone disagrees with the outcome of a Merton assessment, the only route to challenge that finding is to judicially review the decision. Resolving a dispute through judicial review can be a very costly and protracted process, which can absorb significant resources and involve a prolonged period of uncertainty for the young person concerned. A newly established statutory right of appeal will ensure that any challenge to the outcome of an age assessment can be resolved as swiftly as possible.

3. Frequently asked questions

3.1 Why do you intend to use ‘scientific methods’?

Determining the age of a young person is an inherently difficult task. Under current arrangements, where an individual’s age is disputed, local authorities must undertake a ‘Merton-compliant’ age assessment. This typically involves two qualified social workers undertaking a series of interviews with the young person and taking into account any other information relevant to their age. However, even where these assessments are conducted thoroughly and reach reasoned conclusions, they are fraught with difficulty and can have a wide margin of error. We are aware of cases where a Merton assessment has been conducted on the same individual by different social workers, which came to very different conclusions about that person’s age. The use of scientific methods could represent an additional source of evidence to improve decision-making about a person’s age.

3.2 What are the ‘scientific methods’ you’re going to use?

The Home Office is considering a range of methods as a means of providing additional scientific evidence in the age assessment process, but no decisions have been made. Where a method or methods of scientific age assessment is considered to be appropriate, they will be specified in regulations that will be subject to the affirmative procedure.

The UK is one of very few European countries that does not currently employ scientific methods of age assessment – such as X-rays of the teeth, clavicle/collar bone, and the carpal/wrist bones. In addition to this, we are aware of other techniques for assessing age that we will be exploring for potential future use.

3.3 How can you justify the use of scientific methods, given they aren’t accurate and have been discredited?

Given the subjective nature of the current age assessment process, results can vary considerably. The use of scientific methods could represent an additional source of evidence to improve decision-making about a person’s age.

We are aware that there is no single age assessment method (scientific or not) which can determine an individual’s age with precision, and that more than one method may be implemented to provide a more accurate assessment.

The Home Secretary will seek scientific advice directly from the Home Office Chief Scientific Adviser, and determine whether a method, or combination of methods, is appropriate for the purposes of an age assessment. To inform her advice, the Home Office Chief Scientific Adviser has set up an independent Age Estimation Scientific Advisory Committee who have been tasked to review those scientific methods.

3.4 How would you ensure the use of scientific methods are ethical and not harmful to children?

The Home Office has a statutory commitment in relation to safeguarding the welfare of children. We are introducing scientific age assessments to help better protect against adults being treated as children – and ensure vulnerable children can swiftly access the support they need.

The UK is one of very few European countries that does not currently employ scientific methods of age assessment – such as X-rays of the teeth, collar bone, and or wrist bone.

The use of ionising radiation in the UK is highly regulated. We will ensure that any methods used comply with all regulatory requirements and standards and the Age Estimation Scientific Advisory Committee have been asked to advise on the ethical considerations for the use of medical imaging techniques.

There are a number of potential methods that do not involve ionising radiation, which the Home Office is also exploring, but these may require further research and development to support their technical and commercial viability in assessing the ages of age-disputed persons.

3.5. How will you be taking into consideration genetic and environmental factors, such as race, or diet, that may have an effect on things like bone development, and therefore the results of a scientific age assessment?

We are conscious that methods to assess age such as bone development are affected by factors such as ethnicity, body mass, sex, and puberty. We are seeking scientific advice to explore this issue further and any steps we can take to mitigate against these impacts.

3.6 The Home Office says that it will implement scientific methods of age assessment only after seeking scientific advice, but Section 51(9) of the Nationality and Borders Bill suggests that you can implement scientific methods regardless of that scientific advice. Is this just a way for the Home Office to undertake scientific age assessments without proper scrutiny?

There is nothing in existing law which specifically precludes the ability of decision-makers to use scientific methods of age assessment. We are aware of cases where dental X-ray examinations for instance have been used in the past. Section 51(9) clarifies this pre-existing legal position that scientific methods, that may not be specified by the Secretary of State under Section 51(1), may continue to be used where appropriate. However, a negative inference from a person’s refusal to undertake a non-specified method cannot be taken.

3.7 How are you going to ensure that genuine children don’t slip through the net and are classed as adults after age assessment?

We believe the measures we’re planning to introduce will make the system more robust and result in higher quality decisions on people’s age.

As part of these measures, in due course, individuals will also have a full right of appeal (including access to legal aid) to the First Tier Tribunal where they have been assessed as an age other than that claimed. This will provide for independent judicial oversight of the process ensuring the highest standards of decision making are adhered to. In the meantime, individuals will still be able to pursue the existing judicial review process.