The Four Pillars of Medical Ethics

Four principles — autonomy, beneficence, non-maleficence and justice — that give you a shared vocabulary for weighing up any ethical scenario. They are lenses, not a checklist: the skill is spotting where they pull against each other and explaining which should carry more weight here, and why.

Ethics

When to use it

Any ethics station or panel question: consent and refusal, confidentiality, resource allocation, end-of-life care, public-health measures. Use the pillars to organise your thinking, then move quickly to the specifics of the case — interviewers want applied reasoning, not definitions.

The steps

1
Autonomy
Respect a capable person's right to make informed decisions about their own body and care — including decisions others think unwise. Ask: does this person have capacity for this decision? Have they been given the information that matters to them? Are they free from pressure?
2
Beneficence
Act in the patient's best interests. 'Best interests' is wider than the medically optimal option: it includes the person's values, wishes and quality of life as they see it.
3
Non-maleficence
Avoid causing harm, or harm that is disproportionate to the benefit. Almost every intervention carries risk, so the real question is whether the balance of benefit to harm is acceptable — and acceptable to whom.
4
Justice
Treat people fairly and distribute limited resources equitably. Consider fairness to other patients, to society (e.g. infection risk, public money) and whether the decision would be consistent if applied to everyone in the same situation.
5
Weigh the tension and conclude
Name which pillars conflict (e.g. autonomy vs beneficence), say which you think should carry more weight in this case and why, and reach a reasoned, provisional conclusion. Acknowledge what would change your mind.

Worked example

An adult Jehovah's Witness with capacity refuses a blood transfusion after a haemorrhage. Autonomy is central: a capable adult may refuse any treatment, even life-saving treatment, so long as the decision is informed and voluntary. Beneficence pulls the other way — transfusion would likely save their life — and non-maleficence reminds us that forcing treatment on a capable adult is itself a serious harm (and assault). Justice is less central, though we should offer every acceptable alternative (cell salvage, iron, erythropoietin) as we would for anyone. The balance favours respecting the refusal, after confirming capacity, checking the decision is their own and free from pressure, and making sure they understand the consequences.

Try it yourself: A 34-year-old woman who is a Jehovah's Witness has lost a lot of blood after childbirth. She is refusing a blood transfusion, which her doctors believe is necessary to save her life. What should the doctors do?

Common mistakes

Reciting the four definitions and stopping — the marks are in applying them to the case.
Treating the pillars as equal votes to count up rather than weighing them.
Forgetting capacity: autonomy only carries full weight if the person has capacity for that decision.
Ignoring the law and GMC guidance, which usually settle the question in UK practice.

When to use it

The steps

Autonomy

Beneficence

Non-maleficence

Justice

Weigh the tension and conclude

Worked example

Common mistakes

Questions that use this framework