Aidan is ranked as a ‘Leading Junior’ in both the Legal 500 and Chambers UK, where he is recognised as ‘…a master of his profession.’
He specialises in complex clinical negligence, personal injury, disciplinary, insurance, commercial and cross-juridicational work. He acts for claimants and defendants.
In addition to his court work, Aidan has a busy paperwork practice, providing a swift turn-around for pleadings, advice on prospects, tactics and quantum. Aidan regularly represents clients at JSM/RTMs and mediations.
Aidan is an erstwhile contributing editor of ‘The Law of Limitation’ (Bloomsbury Professional).
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Clinical Negligence
Aidan has an extensive medical practice, ranging from complex clinical negligence claims, regulatory discipline and medical product liability. He has a Master’s degree in Healthcare Law & Ethics and has been published in the British Medical Journal.
Aidan represents both claimants and defendants in claims arising from NHS and private treatment:
- Spinal Injuries
- Brain injuries
- Obstetric injuries, including shoulder dystocia
- Consent cases
- Cosmetic surgery
Recent instructions as sole counsel:
- Defending a claim alleging that the improper use of a vaccine led to chronic fatigue syndrome, pleaded at >£7 million.
- Claims arising from allegations of negligent delivery due to excessive traction, causing Erb’s palsy and life-long disabilities, pleaded at >£3.7 million.
- Claim arising from the development of chronic kidney disease following the improper use of medication, pleaded at > £5 million.
- Cauda equina syndrome claim, valued at >£2.5 million.
- Various high-profile claims arising from inappropriate surgery and lack of informed consent, arising from an Orthopaedic Surgeon in private practice.
- Claim arising from a ‘never event’ involving the removal of the wrong bone during surgery.
Personal Injury
Aidan enjoys a busy personal injury practice with a particular focus on:
- Catastrophic injuries
- EL and PL claims
- RTA claims
- Amputation claims
- Fatal accidents
- Clinical negligence
Aidan is frequently instructed to deal with complex evidential issues, allegations of fundamental dishonesty, and quantum disputes.
Aidan regularly conducts conferences with experts, attends JSM/RTMs and fights cases to trial. He is particularly adept at cross examining expert witnesses.
Acting for both claimants and defendants, Aidan has gained useful insight into the approach taken by each side.
International & Travel
Aidan has a busy personal injury and clinical negligence practice, with a cross-jurisdictional dimension. He regularly acts for both claimants and defendants, providing specialist advice and advocacy.
Aidan accepts instructions in respect of a wide range of international injury claims, in respect of road traffic accidents, food poisoning, medical negligence or cosmetic treatments. He also has a wealth of experience of claims involving allegations of fraud and fundamental dishonesty.
Aidan regularly provides bespoke training and seminars for clients, which can be arranged upon request.
Insurance
Aidan regularly acts on behalf of individuals, large businesses and insurance companies in a wide range of high value commercial and contractual disputes. He is frequently instructed to advise on complex issues of law and is lauded for his clear-sighted grasp of practical and commercial considerations. Aidan is noted for his effective courtroom advocacy, especially when dealing with intricate legal issues.
Professional Discipline & Regulation
Aidan has experience in professional disciplinary hearings, across a wide range of sectors. Aidan’s extensive medical practice allows him to provide informed advice and robust representation at medical disciplinary tribunals. He also provides written advice on all aspects of disciplinary and regulatory law.
Aidan also specialises in academic appeals relating to secondary, tertiary and vocational studies. He regularly represents students at disciplinary hearings, arising from accusations of misconduct, ranging from plagiarism, collusion and sexual misconduct. Aidan was recently interviewed for a Radio 4 documentary relating to university misconduct hearings.
Professional Negligence
Aidan has an extensive professional negligence practice, spanning across a range of disciplines, including medicine, law, accountancy, surveyorship and construction. He acts for both claimants and defendants and is recognised for the clarity of his advice and commercial judgment. Aidan has significant experience of mediations, JSM/RTMs and trials.
Sport
Aidan is a member of Chambers’ Sports Disciplinary and Regulatory group. He has extensive experience as an adjudicator, in his capacity as a Judicial Officer for World Rugby, European Professional Cup Rugby (‘ECPR’) and the Rugby Football Union (‘RFU’). Aidan chairs disciplinary panels arising from international test matches, European Cup, Premiership, Championship and National Leagues 1 & 2 fixtures.
Between 2021 and 2025, Aidan sat as a Judicial Member for the Football Association (‘FA’). His role involved hearing cases or appeals in connection with disciplinary and other regulatory processes of the FA, such as anti-doping and integrity.
Aidan also has experience of representing athletes in a range of sporting contexts. He deals with claims arising from contractual, competition and personal injury disputes.
Notable Cases
Education & Qualifications
- BPTC, City Law School, London.
- MA Healthcare Law & Ethics, University of Manchester.
- BA Law & Politics, University of Manchester.
- St Colman’s College Grammar School, Newry, North of Ireland.
Appointments & Memberships
- World Rugby, Judicial Officer.
- Rugby Football Union Judicial Panel.
- Football Association, Judicial Panel Member (2021-2025).
- British Association for Sport & Law.
- Personal Injuries Bar Association (PIBA).
- Association of Personal Injury Lawyers (APIL).
To instruct Aidan O’Brien or obtain more information
Our clerking team, led by Chief Executive & Director of Clerking, Paul Cray, will be pleased to help with any enquiry regarding Aidan O’Brien , including suitability, availability, and fees. The team offers responsive, commercially focused, and highly professional support.