Gillick Competence Explained: Consent and Under-16s
Gillick competence is the legal test used across the UK to assess whether a person under 16 has the maturity and understanding to consent to their own medical treatment without a parent's involvement. It comes from the 1985 House of Lords case Gillick v West Norfolk and Wisbech Area Health Authority, and it remains the standard UK healthcare professionals actually apply today.
A child under 16 can legally consent to their own medical treatment if they have "sufficient understanding and intelligence to fully understand what is proposed," judged for that specific decision, not by age alone.
Where does the term come from?
The case involved a mother, Victoria Gillick, who challenged Department of Health guidance allowing doctors to provide contraceptive advice to under-16s without parental knowledge or consent. She argued this undermined parental rights and encouraged under-age sexual activity. The House of Lords disagreed by a narrow 3-2 majority, ruling that a child under 16 can consent to their own treatment, provided they have sufficient understanding of what's proposed. That single sentence is the entire basis of the test still used decades later.
Gillick v West Norfolk and Wisbech Area Health Authority [1985] UKHL 7 — the House of Lords ruling that established the test, still cited by name in current professional guidance across UK healthcare regulators.
Why the ruling was genuinely close, and why that still matters
It's easy to treat Gillick as a settled, uncontroversial principle now, but the original judgment was decided 3-2, and the two dissenting Law Lords argued a fixed age threshold would have given doctors and families far more certainty. That disagreement hasn't fully gone away: the flexibility that makes Gillick genuinely responsive to a young person's actual maturity is the same flexibility that makes it harder to apply consistently than a clean age cutoff would be. Understanding that tension is part of understanding why documentation matters so much, covered further down.
The four things a genuine assessment must establish
There's no fixed checklist or age threshold, it's a judgement made for each specific decision, with each individual young person. A healthcare professional needs to assess whether the young person genuinely understands each of the following, and a real assessment addresses all four, not just the first that comes to mind.
What the treatment actually involves
Not a simplified summary, genuine understanding of what will actually happen.
The benefits, risks, and alternatives
Including what happens if they choose a different option, or none at all.
The likely consequences of declining treatment
A genuinely informed decision requires understanding the cost of saying no, too.
That the information applies specifically to them
Abstract understanding of a concept isn't the same as applying it to their own situation.
Crucially, this assessment is decision-specific, not a general "is this child mature" judgement. A 14-year-old might be Gillick competent to consent to a straightforward, low-risk treatment while genuinely not having sufficient understanding for a more complex decision with serious, less reversible consequences. The same young person can be competent for one decision and not another, in the same appointment.
Gillick, Fraser, and standard adult consent compared
These three terms are often used loosely and interchangeably, which is exactly where confusion creeps in. Seeing them side by side makes the actual scope of each clearer.
| Test | What it applies to | Key condition |
|---|---|---|
| Gillick competence | Any medical treatment decision involving a person under 16 | Sufficient understanding of that specific decision |
| Fraser Guidelines | Contraceptive advice and treatment specifically | Understanding, plus likely to proceed with or without help, plus health at risk without it |
| Standard adult consent | Anyone 16 or over | Capacity presumed unless shown otherwise |
Does Gillick competence apply the same way to refusal?
This is where the standard becomes genuinely more complicated, and it's a common point of confusion. While a Gillick competent young person can consent to treatment independently, the position on refusing treatment is legally less settled, particularly where refusal could result in serious harm. In practice, this means a refusal by a competent young person is treated with real weight but doesn't automatically carry the same legal finality that consent does, and often warrants a more cautious, collaborative approach involving parents where possible.
A 15-year-old attends a sexual health clinic alone, requesting contraception, and asks that her parents not be informed. The nurse assesses that she understands the treatment, its risks, and the implications clearly, and that she's likely to proceed with or without the nurse's help, satisfying the Fraser criteria specifically. The nurse proceeds, encourages the young person to consider involving a trusted adult, and documents the assessment clearly, including the specific reasoning for finding her competent for this particular decision.
What good documentation of this assessment actually looks like
A generic note stating "assessed as Gillick competent" carries little weight if it's ever scrutinised later, precisely because the 1985 ruling itself was contested and depends on a judgement call, not a fixed rule. A defensible record specifically states what was explained, what the young person demonstrated they understood in their own words, and why that met the threshold for that particular decision, not just the conclusion reached. Recording the reasoning is what actually protects both the young person's autonomy and your own professional judgement if the decision is ever questioned later.
