Ten Common Mistakes in Age Assessments and How to Avoid Them

A practical guide for social workers conducting Merton-compliant age assessments

Age assessments are among the most challenging and consequential tasks undertaken by social workers. When conducted on unaccompanied asylum-seeking children, these assessments determine whether a young person receives vital child protection services or is treated as an adult. The stakes couldn't be higher, and the margin for error is slim.

Since the landmark Merton judgment in 2003, the courts have consistently emphasised the need for rigorous, fair, and well-documented age assessments. Yet even experienced practitioners can fall into common pitfalls that leave their assessments vulnerable to legal challenge. In this post, we'll explore the most frequent mistakes and provide practical strategies to avoid them.

1. Failing to Give the Young Person the Benefit of the Doubt

The Mistake

Many assessors approach age assessments with scepticism, looking for evidence that the young person is lying rather than starting from a position of openness. This subtly shifts the burden of proof onto the young person, contradicting established legal principles.

Why It Happens

• Pressure from resource-constrained local authorities

• Previous experiences with dishonest claims

• Cultural misunderstandings that create false impressions of deception

• Lack of awareness about trauma's impact on presentation

The Impact

The Court of Appeal has repeatedly emphasised that where there is doubt, the young person should be treated as a child. Assessments that fail to demonstrate this principle are vulnerable to judicial review.

How to Avoid It

Document your starting position. Begin your assessment report with a clear statement: "We approached this assessment with an open mind, applying the benefit of the doubt principle where uncertainty exists."

Actively look for evidence supporting the claimed age as well as evidence that might contradict it. Your report should demonstrate balanced inquiry, not an investigation designed to disprove the young person's account.

Be explicit about uncertainty. When you're not sure about something, say so. Phrases like "on balance" or "the weight of evidence suggests" show appropriate professional humility and strengthen rather than weaken your assessment.

Consider trauma. Remember that traumatised young people may present as older (through hypervigilance, emotional flatness, or premature responsibility-taking) or younger (through regression). Factor this into your analysis.

2. Over-Relying on Physical Appearance

The Mistake

Placing disproportionate weight on physical appearance and development when determining age, without acknowledging the huge variation in how young people develop.

Why It Happens

• Physical appearance is immediately observable and seemingly objective

• Lack of understanding about developmental variation across populations

• Influence of subconscious biases about what children "should" look like

• Pressure to make quick decisions

The Impact

Research consistently shows that visual assessments of age are unreliable, with error margins of several years. Courts have criticised assessments that rely heavily on appearance without adequate caveats.

How to Avoid It

Never rely on appearance alone. The Merton judgment is clear: physical appearance is just one factor among many. Your assessment must be holistic.

Acknowledge variation explicitly. Include statements like: "We recognise that physical development varies significantly between individuals and across different populations. Height, build, and secondary sexual characteristics are not reliable indicators of age in isolation."

Be specific about observations. Rather than vague statements like "appears mature," document specific observations: "Has developed facial hair on upper lip and chin" or "voice has fully broken." Then acknowledge that these features can develop across a wide age range.

Consider context. Malnutrition, stress, and hard physical labour can all accelerate physical maturation. Document any evidence of these factors in the young person's history.

Document your uncertainty. If physical appearance is ambiguous (as it often is), say so clearly. "While [name] has some physical characteristics that could be consistent with someone older than 17, these characteristics are also seen in some 16 and 17-year-olds."

3. Insufficient Exploration of the Journey

The Mistake

Rushing through or inadequately documenting the young person's journey to the UK, missing crucial detail that could corroborate their account or reveal inconsistencies.

Why It Happens

• Discomfort asking about potentially traumatic experiences

• Time pressures

• Language and interpretation challenges

• Assuming other interviews you may have read covers this adequately

The Impact

The journey often contains rich detail that helps establish credibility. Without thorough exploration, you lose opportunities to assess consistency, plausibility, and the young person's developmental level at the time of departure.

How to Avoid It

Allocate sufficient time. Journey exploration should take 60-90 minutes minimum. Schedule it strategically (we recommend before lunch on Day 1, so the young person has recovery time afterward).

Go country by country. For each country or significant location, ask:

• How did you get there?

• How long were you there?

• Where did you stay?

• Who looked after you?

• What did you do there?

• How did you leave?

Document agency. Did the young person make decisions, or were they passive? This reveals developmental maturity.

Note spontaneous detail. Specific, unsolicited details (smells, colours, names, emotions) suggest genuine memory rather than rehearsed narrative.

Allow silence. Don't rush to fill pauses. Traumatic memories take time to access.

Return to it on Day 2 if needed. Brief clarification questions at the start of Day 2 show thoroughness without re-traumatising.

4. Inadequate Assessment of Education

The Mistake

Accepting surface-level information about schooling without probing for the specific, verifiable details that reveal genuine educational experience.

Why It Happens

• Lack of knowledge about education systems in other countries

• Accepting "I went to school" as sufficient information

• Not recognising the difference between vague and specific educational memories

The Impact

Educational history is one of the strongest age indicators when properly explored. Superficial questioning wastes this opportunity and weakens your assessment.

How to Avoid It

Ask for specifics:

• Names of schools and teachers

• Description of the building and journey to school

• Subjects studied and what was learned

• Friends' names and what they did together

• Uniform details

• Daily routine (arrival time, break times, end time)

• Homework and exams

• Best and worst subjects and why

Check for age-appropriate experiences. Starting school, first day memories, and progression through grades should align with claimed age.

Look for spontaneous detail. Genuine memories include sensory details, emotions, and incidental information that's hard to fabricate.

Cross-reference. Educational experiences should be consistent with other parts of the narrative (family life, responsibilities, reasons for leaving school).

Document gaps. If education was interrupted, understand why and at what age. This context is crucial.

5. Poor Documentation of the Assessment Process

The Mistake

Failing to record the assessment process adequately, including breaks taken, observations made, and the young person's demeanour throughout.

Why It Happens

• Focus on content over process

• Time pressures

• Assumption that only the final report matters

• Not recognising that process demonstrates Merton compliance

The Impact

Courts can and do quash age assessments where the process isn't adequately documented, even if the conclusion might have been correct. You need to show you followed proper procedure.

How to Avoid It

Document everything:

• Start and end times for each section

• Breaks taken (when, how long, what was provided)

• Emotional responses and when they occurred

• Body language and engagement levels

• Use of interpreter

• Questions asked and exact responses (including hesitations, corrections, and non-verbal communication)

Record your reasoning in real-time. Don't wait until writing the final report to analyse what you heard. Contemporary notes are more credible.

Note when you applied the benefit of the doubt. Show your decision-making: "We considered whether [name]'s difficulty recalling dates might indicate deception, but concluded that given their limited formal education and the trauma they experienced, this was equally consistent with their claimed age."

Use exact quotes. Particularly when the young person uses phrases that seem rehearsed or coached, or conversely, when they use language that seems genuinely childlike.

Both assessors should take notes. Two sets of contemporaneous notes strengthen your assessment's credibility even if limited.

6. Failing to Conduct a 'Minded To' Discussion

The Mistake

Reaching a conclusion that the young person is older than claimed without first giving them an opportunity to respond to your concerns.

Why It Happens

• Lack of awareness about this procedural requirement

• Concern it will be confrontational or distressing

• Belief that it's unnecessary if the evidence seems clear

• Time pressures

The Impact

This is a serious procedural flaw that can render an entire assessment unlawful. The Supreme Court in R (A) v Croydon LBC [2009] confirmed that fairness requires the young person be given an opportunity to address concerns before a final decision.

How to Avoid It

Build it into your schedule. Allocate 20-30 minutes on Day 2 afternoon for a 'minded to' discussion if needed.

Be clear but respectful. Explain: "Based on what we've discussed, we have some concerns about the age you've told us. Before we make any decision, we want to share our thinking and give you a chance to respond."

Be specific. Don't make vague accusations. Reference specific observations or inconsistencies: "You mentioned you were 14 when you left school, but you also said you completed [grade level], which typically happens at age 16-17 in your country."

Allow adequate time to respond. The young person needs time to process and reply, especially through an interpreter.

Document thoroughly. Record what concerns you raised, how you raised them, and what the young person said in response.

Consider their response seriously. Sometimes the young person provides information that explains apparent inconsistencies. Factor this into your final decision.

7. Ignoring Cultural Context

The Mistake

Interpreting experiences, behaviours, and developmental markers through a British or Western lens without considering cultural differences.

Why It Happens

• Lack of cultural competency training

• Unconscious bias

• Limited exposure to diverse cultural practices

• Time constraints preventing proper research

The Impact

Cultural misunderstandings can lead to fundamentally flawed assessments. Experiences that seem inconsistent with childhood in Britain may be entirely normal in the young person's culture.

How to Avoid It

Research the country of origin. Before the assessment, learn about:

• Education system (when school starts, typical progression, leaving age)

• Cultural practices around childhood and coming of age

• Common naming practices

• Calendar systems (Gregorian, Islamic, Ethiopian, etc.)

• Typical childhood responsibilities

• Cultural attitudes to age and birth dates

Ask about cultural norms. "In your country, what age do children typically start school?" or "How do families in your area celebrate birthdays?"

Don't assume. Never assume that childhood in another country looks like childhood in Britain. Children in many cultures take on substantial responsibilities at young ages.

Consult country experts. For complex cases, consider consulting with country experts or refugee organisations familiar with the specific context.

Acknowledge limitations. If you're not confident about cultural context, say so in your report and explain how you've tried to address this gap.

8. Poor Assessment of Internal Consistency

The Mistake

Either accepting inconsistencies too readily or treating every minor inconsistency as evidence of dishonesty, without proper analysis.

Why It Happens

• Black-and-white thinking (either everything is consistent or the person is lying)

• Lack of understanding about memory and trauma

• Pressure to find evidence supporting a predetermined conclusion

• Insufficient time spent analysing the narrative as a whole

The Impact

Inconsistencies need careful analysis. Some are significant, some are explained by trauma or memory limitations, and some are translation issues. Failing to analyse them properly weakens your assessment.

How to Avoid It

Distinguish between types of inconsistency:

• Minor inconsistencies (slight date variations, peripheral details) are normal and expected

• Significant inconsistencies (contradictions about major events or timeline) require exploration

• Explained inconsistencies (person acknowledges and explains) may not undermine credibility

Consider alternative explanations:

• Trauma affecting memory

• Translation and interpretation issues

• Misunderstanding the question

• Different calendar systems

• Genuine correction as memories become clearer

Return to inconsistencies. Don't just note them and move on. Say: "Earlier you mentioned [X], but now you've said [Y]. Can you help me understand this?"

Look for overall coherence. Does the narrative make sense as a whole, even if some details vary? Real memories are often consistent in core elements but vary in peripheral details.

Document your analysis. Show your reasoning: "While [name] was inconsistent about the exact month they left [country], they were consistent about the circumstances of leaving, who they were with, and how they travelled. We do not consider this minor date inconsistency to undermine their overall credibility."

9. Insufficient Attention to Demeanour and Interaction Style

The Mistake

Either over-interpreting demeanour as evidence of deception or failing to consider it at all in the holistic assessment.

Why It Happens

• Misconceptions about how truthful or deceptive people behave

• Cultural differences in communication styles

• Lack of training in non-verbal communication

• Trauma's impact on presentation not being considered

The Impact

Demeanour is a relevant factor but must be interpreted carefully. Both over-reliance and complete disregard weaken assessments.

How to Avoid It

Observe and record systematically:

• Eye contact patterns (noting cultural norms vary)

• Body language and posture

• Emotional responses and when they occur

• Engagement level throughout the assessment

• How they interact with the interpreter

• Signs of distress or dissociation

Avoid stereotypes. Lack of eye contact doesn't indicate lying. Emotional flatness doesn't mean the story isn't true. These can all be trauma responses or cultural communication styles.

Consider context. Is the young person exhausted? Frightened? In an unfamiliar setting with strangers asking intimate questions? This affects presentation.

Look for congruence. Do emotional responses match the content discussed? Becoming emotional when discussing family separation is congruent and suggests genuine experience.

Note changes. Did the person become more relaxed as the assessment progressed? This suggests genuine engagement rather than maintaining a false narrative.

Balance with other evidence. Demeanour is one piece of a complex puzzle, not the answer in itself.

10. Inadequate Final Analysis

The Mistake

Listing observations and information without synthesising them into a coherent analysis that explains how you reached your conclusion.

Why It Happens

• Time pressures to complete reports

• Belief that listing evidence is sufficient

• Difficulty articulating complex reasoning

• Assumption that conclusions are self-evident

The Impact

Courts expect to see clear reasoning linking evidence to conclusions. A list of facts without analysis doesn't demonstrate the careful consideration required by Merton.

How to Avoid It

Include a dedicated analysis section. After presenting your findings, have a section titled "Analysis" or "Assessment of Age" that brings everything together.

Address each key factor explicitly:

• Physical appearance and development

• Interaction and demeanour

• Educational history

• Family and social circumstances

• Journey narrative

• Cultural factors

• Internal consistency

• External consistency (with country information)

Explain your reasoning. Don't just state "the education history is inconsistent with claimed age." Explain: "The young person described completing [grade level], which in [country] typically occurs at age 16-17. They also described studying [advanced subjects] that are not part of the curriculum for younger students. This suggests they were older than the claimed age of 15 when they left school."

Address contrary evidence. If some factors support the claimed age while others don't, say so and explain which factors you've given more weight and why.

Be clear about your conclusion. State whether you assess the person as the age they claim, older, or younger, and if older/younger, what age you assess them to be (or age range).

Explain how you applied the benefit of the doubt. If there was uncertainty, explain how you resolved it in the young person's favour or why the evidence was sufficiently clear to overcome doubt.

Key Principles to Remember

Throughout your age assessment, keep these principles front of mind:

1. Start with an open mind. Presume the young person is the age they claim unless clear evidence suggests otherwise.

2. Be thorough. Allocate adequate time (typically two full days) to gather sufficient information with additional time prior for research.

3. Document everything. Contemporary notes, observations, and reasoning strengthen your assessment.

4. Think holistically. No single factor determines age. Consider all evidence together.

5. Acknowledge uncertainty. Professional humility strengthens rather than weakens your credibility.

6. Be culturally informed. Research, ask questions, and avoid imposing British norms.

7. Consider trauma. It affects memory, behaviour, development, and presentation.

8. Follow procedure. Merton compliance isn't optional. Shortcuts lead to quashed assessments.

9. Give the benefit of the doubt. When in doubt, treat the person as a child.

10. Write clearly. Your report should be understandable to non-specialists, including judges.

Conclusion

Age assessments are complex, high-stakes processes that require skill, sensitivity, and rigorous attention to procedure. By avoiding these common mistakes, you'll produce assessments that are not only Merton-compliant but also fair, thorough, and defensible.

Remember: a well-conducted age assessment protects children who need protection while maintaining the integrity of the system. Taking the time to do it properly benefits everyone involved.

Need help ensuring your age assessments are Merton-compliant?

Our comprehensive age assessment template provides a structured, two-day interview framework that incorporates all the principles discussed in this article. Designed by experienced practitioners, it helps you avoid common pitfalls and conduct assessments that withstand legal scrutiny.

Further Reading

• R (B) v Merton London Borough Council [2003] EWHC 1689 (Admin) - The foundational judgment

• R (A) v Croydon London Borough Council [2009] UKSC 8 - Supreme Court guidance on procedural fairness

• R (FZ) v Croydon London Borough Council [2011] EWCA Civ 59 - Court of Appeal on the benefit of the doubt principle

• Association of Directors of Children's Services: Age Assessment Guidance (2015)

• Royal College of Paediatrics and Child Health: Position Statement on Age Assessment (2023)

This article is for informational purposes only and does not constitute legal advice. Age assessments should always be conducted by qualified social workers in accordance with current guidance and case law.

About the Author: Matt Vincent has over 10 years experience conducting and managing age assessments for local authorities and organisations. Independent Migrant Services provides training, templates, and resources to support social workers conducting Merton-compliant age assessments.

Age Assessment Template