Common Defences in Medical Negligence Claims in Ireland: What the Other Side Will Argue
Author: Gary Matthews, Principal Solicitor, Law Society of Ireland PC No. S8178 • 3rd Floor, Ormond Building, 31-36 Ormond Quay Upper, Dublin D07 • 01 903 6408 • Published
Defences in medical negligence claims are the legal arguments that hospitals, doctors, and the State Claims Agency use to defeat or reduce your claim for compensation in Ireland. Every medical negligence case in Ireland faces at least some of these defences. The most common are: that the treatment followed accepted practice (the Dunne defence), that the negligence did not cause the injury (causation failure), that the patient contributed to the harm (contributory negligence), and that the claim was brought too late (statute of limitations). None of these defences is insurmountable, but each requires specific evidence to overcome.
The main defences raised in Irish medical negligence claims include compliance with general and approved practice under the Dunne principles, causation failure, contributory negligence under Section 34 of the Civil Liability Act 1961, statute of limitations, inherent risk, and informed consent adequacy. The State Claims Agency (SCA) manages the defence of all public hospital claims in Ireland, with estimated outstanding clinical liabilities of €5.35 billion according to the SCA Annual Report 2024. Understanding these defences before you begin your claim is the difference between building a case that survives challenge and one that collapses at the first hurdle.
What's new (2025/2026): Perez v Coombe [2025] confirmed clinical guidelines are guidance, not mandatory rules. The Supreme Court in Kirwan v Connors [2025] IESC 21 revised the delay-dismissal framework, introducing tiered thresholds at 2, 4, and 5 years. The Patient Safety Act 2023 commenced on 26 September 2024, making open disclosure mandatory but not admissible as evidence (s.10).
At a glance: Irish hospitals and the SCA typically raise 8 to 10 standard defences. None automatically defeats your claim. Each has a specific counter-strategy grounded in Irish case law. The key defences are: Dunne-compliant practice, causation failure (but-for test), contributory negligence (reduces but does not defeat), statute of limitations, inherent risk, informed consent, delay in prosecution, and the open-disclosure non-admission rule under the Patient Safety Act 2023.
Not all defences are equal. Prioritise your evidence accordingly:
Case-ending defences (can kill the entire claim): causation failure, statute of limitations, Section 26 exaggeration, delay/want of prosecution.
Damages-reducing defences (the claim survives but the award falls): contributory negligence, pre-existing condition.
Routinely raised defences (standard first-line arguments, rarely decisive alone): approved practice (Dunne), inherent risk, honest difference of opinion, informed consent adequacy, guidelines-not-rules, open disclosure non-admission.
If your solicitor identifies a case-ending defence as the likely battleground, your expert evidence must address that defence first. A case that is strong on breach but weak on causation is a case that loses.
Contents
What Is the Dunne Defence in Medical Negligence?
The most common defence in Irish medical negligence cases argues that the treating practitioner followed a practice accepted by a substantial number of reputable peers of the same specialisation. The Dunne principles, established by the Supreme Court in Dunne v National Maternity Hospital [1989] IR 91 and reaffirmed in Morrissey v HSE [2020] IESC 6, set the legal standard for assessing medical negligence in Ireland. A defendant who proves they followed "general and approved practice" in a surgical negligence claim or any other clinical negligence case has, on the face of it, a strong defence.
The critical exception is Dunne Principle 3: even a widely followed practice can be found negligent, if it has "inherent defects which ought to be obvious to any person giving the matter due consideration." A practice followed by every colleague in the country is still negligent, if it is fundamentally flawed. Your expert report must identify the specific defect in the practice, not simply say they would have done things differently.
One detail that catches many claimants off guard: a defendant does not need to show that every doctor agrees with their approach. The practice need only be "general and approved," meaning adopted by a substantial number of reputable practitioners. Where two reasonable approaches exist, the defence wins, even if the other approach might have produced a better result.
Can an Honest Difference of Opinion Defeat a Claim?
An honest disagreement between doctors about which of two valid treatment approaches is preferable does not establish negligence under Irish law. Dunne Principle 5 makes clear that courts do not choose between two reasonable options. They assess only whether the chosen approach met the standard of a competent practitioner of equal skill. The defence regularly uses this principle where clinical judgment calls were involved, such as choosing one surgical technique over another or deciding when to intervene.
You overcome this defence by showing that the treatment chosen falls outside all accepted approaches, not that an alternative was better. The question is not "would a different doctor have done something else?" It is "would any competent doctor in that specialty have done what this doctor did?"
↑ Back to topHow Does Causation Failure Work as a Defence?
Causation is the defence that defeats more valid claims than any other single argument in Irish medical negligence litigation. In our experience advising claimants across a range of specialties, even where breach is conceded, the defendant argues the patient's outcome would have been the same regardless of the negligent act or omission. The claimant must prove, on the balance of probabilities, that the injury would not have occurred but for the breach.
The "but-for" test in practice
Irish courts apply a straightforward question: would this injury have happened anyway? A delayed cancer diagnosis may seem clearly negligent, but the defence argues the cancer was already terminal when the patient first presented. Expert evidence on staging, survival statistics, and treatment options at the earlier date is essential. Without it, the breach is proven but the claim fails on causation.
Loss of chance: unsettled Irish law
The position on loss of chance in Ireland remains uncertain. In Philp v Ryan [2004] IESC 105, the Supreme Court allowed a proportional damages approach, awarding compensation for the plaintiff's loss of life expectancy caused by a delayed prostate cancer diagnosis. Six months later, the Supreme Court in Quinn v Mid Western Health Board [2005] seemingly required full but-for proof without referencing Philp. The difference between assessment on statistics and what a claimant must prove on the balance of probabilities is exactly where many delayed-diagnosis claims stumble. A clear expert opinion on how much the delay changed the odds, not just that it "reduced the chances," is vital. See our guide to proving causation in medical negligence.
Key takeaway: the three defences above work together. The Dunne defence says the doctor followed accepted practice. The honest-opinion defence says two approaches existed and the doctor chose one. Causation failure says the outcome would have been the same regardless. In a typical Irish medical negligence claim, the State Claims Agency raises all three in its defence. Your expert report must address each: (1) the treatment fell outside all accepted approaches, not merely that an alternative existed; (2) Dunne Principle 3 applies because the practice had an inherent defect obvious on due consideration; and (3) if the correct treatment had been given at the correct time, the patient's outcome would, on the balance of probabilities, have been materially different. A claim that addresses only one of these three defences is vulnerable to the other two.
Does Contributory Negligence Defeat a Medical Negligence Claim?
Contributory negligence reduces your award but does not defeat your claim. Under Section 34 of the Civil Liability Act 1961, the court reduces damages by "such amount as the court thinks just and equitable having regard to the degrees of fault." Defendants commonly argue that the patient failed to attend follow-up appointments, did not take prescribed medication, delayed seeking medical attention, or ignored post-operative instructions.
The burden falls on the defendant to prove your conduct contributed to the harm. Document everything: keep appointment confirmations, request your full medical records, and any correspondence with your treating team. Where degrees of fault cannot be established, liability is split equally under Section 34(1)(a).
Typical apportionment ranges in medical negligence
Irish courts have applied contributory negligence reductions ranging from 10% to 50% in personal injury cases, with medical negligence reductions typically falling at the lower end of that range. From handling these cases in Irish courts, the common scenarios and their likely reductions include: failure to attend a follow-up appointment (10 to 20% reduction), delayed presentation to a GP when symptoms were present (15 to 25%), non-compliance with a prescribed treatment plan such as physiotherapy or medication (10 to 33%), and failure to disclose relevant symptoms or medical history during a consultation (10 to 20%). These figures are not fixed. They reflect the court's assessment of what is "just and equitable" in the individual case. Awards themselves follow the Judicial Council Personal Injuries Guidelines. A patient who missed one appointment faces a different reduction to one who ignored repeated warnings over several months. Your solicitor will advise on the likely range based on the specific facts of your case.
Ireland vs England and Wales: In England and Wales, contributory negligence follows the Law Reform (Contributory Negligence) Act 1945. The Irish provision under the 1961 Act operates differently and applies specifically to Irish proceedings. UK-based guides applying the 1945 Act do not reflect the Irish position.
Inherent Risk and Known Complications
The inherent risk defence argues that the complication was a recognised possibility of the procedure, not the result of negligent care. In our experience, defendants use this defence as a first-line response in nearly every surgical negligence claim. An infection rate of 1 to 2% in surgery is statistically expected. The fact that an infection occurred does not, on its own, prove negligence.
You defeat this argument by distinguishing between the statistical risk and the specific clinical facts. An infection linked to documented breaks in sterile technique, or one that went undiagnosed for weeks despite clear signs, is a different matter from a complication that arose despite textbook care. Your expert report must connect the complication to a specific departure from the Dunne standard, not simply describe the statistical risk.
What Are the SCA's Three Standard Consent Arguments?
In consent-based claims, the State Claims Agency typically deploys three specific arguments to defeat the case. We see all three raised together in virtually every consent claim we handle. Irish law applies the patient-centred test from Fitzpatrick v White [2007] IESC 51, as explained in the BAILII judgment text: a doctor must disclose any risk that a reasonable person in the patient's position would consider significant. The defence counters with:
- Causation defeat: "The patient would have proceeded regardless." You must prove you would not have consented had you been properly informed.
- Verbal disclosure: "The risk was discussed, even if the consent form does not record it." Contemporaneous notes from both sides become decisive.
- Materiality challenge: "The undisclosed risk was not 'material' for this particular patient." Evidence of your specific concerns, lifestyle, and expressed preferences counters this.
Signing a consent form does not bar a claim. Courts look at what was actually communicated, not just what was signed. The gap between what was written and what was said in the room is where many consent cases turn. See our detailed guide to informed consent failures under Fitzpatrick v White.
Two independent legal routes: standard of care and informed consent
Irish law provides two separate grounds for a medical negligence claim, and each operates independently. The standard of care route (Dunne v NMH [1989]) addresses whether the treatment itself was negligent. The informed consent route (Fitzpatrick v White [2007]) addresses whether material risks were properly disclosed before the patient agreed to treatment. Both can be pursued simultaneously in the same proceedings. The defence may defeat one and still lose on the other. A surgeon who performed a procedure competently may still be liable, if a material risk was not explained and the patient would have declined the procedure had they known. Equally, a patient who was fully informed may succeed on the standard of care route, if the procedure was carried out negligently. The practical consequence is that your solicitor and expert should address both pathways from the outset, because the defence will try to close each one separately.
↑ Back to topKey takeaway: four defences target the treatment itself, not the timeline. Inherent risk says the complication was a known possibility. Contributory negligence says the patient's own actions made the outcome worse. The consent defence says the patient was warned and would have proceeded anyway. The dual-pathway rule means the SCA can defend on both the Dunne standard and informed consent independently, and winning on one does not guarantee losing on the other. Your evidence strategy must treat these as separate battles: operative notes and expert opinion address inherent risk, your attendance and compliance records address contributory negligence, and a clear account of what you were told (and what you were not) addresses consent. Failing to prepare evidence on any one of these leaves a gap the defence will exploit.
Can the Statute of Limitations Bar Your Claim?
The limitation period for medical negligence claims in Ireland is two years less one day from the date of knowledge, not the date of treatment. This is the single most common reason we see potentially valid claims fail. The Statute of Limitations (Amendment) Act 1991 governs this deadline. Defendants regularly argue that the plaintiff knew or ought to have known about the injury and its negligent cause more than two years before proceedings were issued.
Your "date of knowledge" is when you first became aware that you suffered a significant injury attributable to another party's negligence. Receipt of an expert medical report is often the trigger. In O'Sullivan v Ireland [2019] IESC 33, the Supreme Court upheld a claimant's argument that knowledge only arose when an expert confirmed the link between treatment and injury.
Critical difference from England: The English limitation period for clinical negligence is three years. The Irish period is two years. Online guides and UK-based legal resources frequently state "three years," which is wrong for Ireland. Medical negligence claims are also exempt from the IRB process, so the PIAB suspension mechanism does not apply. Your clock stops only when court proceedings are issued.
For the full analysis, see our guide to medical negligence time limits in Ireland.
Can Your Case Be Dismissed for Delay?
Irish courts now dismiss medical negligence claims more readily for delay, following the Supreme Court's revised framework in Kirwan v Connors. The old Primor test (Primor plc v Stokes Kennedy Crowley [1996]) required three steps: inordinate delay, inexcusable delay, and a balance of justice favouring dismissal. The Supreme Court has now tightened the approach:
- 2+ years of delay: The court may dismiss, though it is not automatic.
- 4+ years of delay: The case should be dismissed unless the plaintiff gives a convincing explanation for why a fair trial is still possible.
- 5+ years of delay: Wide discretion to dismiss, except for strong reasons of fairness or public interest.
Separately, in O'Neill v Birthistle, the High Court dismissed a medical negligence claim because the plaintiff served proceedings while holding an unsupportive expert report. Even though a supportive report was later obtained, the court ruled this was an abuse of process. The Cooke v Cronin line of authority makes clear that it is irresponsible to launch medical negligence proceedings without expert advice supporting them. The lesson from cases we have handled: never let your case file go dormant, and do not issue proceedings without credible expert support. See our guide on why expert medical evidence is essential.
↑ Back to topKey takeaway: three defences can kill your claim entirely on procedural grounds. The statute of limitations bars any medical negligence claim in Ireland brought more than two years less one day after the date of knowledge. The delay-dismissal framework from Kirwan v Connors [2025] IESC 21 means courts will now dismiss claims where proceedings have been dormant for four or more years, even without evidence of specific prejudice to the defendant. And issuing proceedings without a supportive expert report is an abuse of process under the Cooke v Cronin line of authority. All three are avoidable. Act within the limitation period, keep your case file moving at all times, and do not serve proceedings until you have an expert opinion that supports your claim. These are not technicalities. They are the most common reasons valid Irish medical negligence claims fail before they reach trial. See our guide on how long a medical negligence claim takes.
Is an Apology from a Hospital an Admission of Fault?
An apology or disclosure meeting under the Patient Safety (Notifiable Incidents and Open Disclosure) Act 2023 cannot be used as evidence in court and does not constitute an admission of fault. Section 10 of the Act explicitly provides this protection. The Act, which passed all stages in the Oireachtas and commenced on 26 September 2024, requires mandatory disclosure of specified serious incidents, including wrong-site surgery, medication errors causing death, and unanticipated deaths linked to treatment.
One aspect the official guidance does not cover directly: claimants often believe that a hospital's apology proves their case. Legally, the opposite applies. Open disclosure tells you something went wrong. It is a starting point for investigation, not proof of negligence. You still need independent expert evidence to establish breach and causation. Use the disclosure as a guide to what to investigate, not as evidence to present.
Do Clinical Guidelines Set the Legal Standard?
Departure from a clinical guideline does not, by itself, prove negligence under Irish law. The High Court confirmed this in Perez v Coombe Women and Infants University Hospital [2025], ruling that clinical guidelines such as IMEWS, RCOG, and NICE are "guidance tools only, not mandatory rules." The Dunne test remains the legal standard. The Citizens Information guide to health service complaints explains the distinction between a care standards concern and a legal claim.
Many claimants and families anchor their case on "they did not follow the guidelines." The defence pulls this ground away by arguing that the guideline was one factor, not the decisive factor. To counter it, your expert must go further: explain why departure from the guideline fell below the Dunne standard in the specific clinical circumstances. Guidelines are strong evidence of what competent practice requires, and departure from them shifts the evidential burden, but they are not a shortcut to proving breach.
Pre-Existing Conditions
Defendants argue the patient's pre-existing condition, not the treatment, caused the deterioration. Where a patient had an underlying disease, the defence contends that the natural progression of illness explains the outcome. Expert evidence comparing the likely trajectory with and without the breach is essential. A condition that was manageable before negligent treatment but catastrophic afterwards points to causation, even with a pre-existing baseline. The difference between what was expected and what actually happened is what the expert must quantify.
↑ Back to topThe Exaggeration Defence Under Section 26
The court must dismiss your entire claim, if you give evidence that is misleading or materially exaggerated, under Section 26 of the Civil Liability and Courts Act 2004, unless dismissal would result in an injustice being done. This is not a proportional reduction like contributory negligence. It is, in practice, a complete defeat of the claim. The section applies where a plaintiff gives or adduces evidence that is "false or misleading in any material respect" and the court is satisfied that the plaintiff "knew it to be false or misleading." The injustice exception is narrow and rarely succeeds. Defendants raise this defence proactively. The SCA and private insurers routinely commission surveillance evidence, review social media activity, and cross-reference medical records against the claimant's stated symptoms.
The timing matters more than most guides suggest: surveillance is often commissioned after proceedings are issued but before mediation or trial. A claimant who describes being unable to walk but is filmed running a 5K faces not just a reduction in damages but the loss of the entire case. The distinction between putting your best case forward and materially overstating your injuries is where Section 26 operates. Be accurate in every medical appointment, every affidavit, and every interaction with the other side's medical examiner.
How the State Claims Agency Actually Defends Claims
The SCA manages all clinical negligence claims against the HSE under the Clinical Indemnity Scheme, controlling settlement authority, expert selection, and litigation strategy. According to the State Claims Agency Annual Report 2024, the Agency paid €210.5 million in clinical care damages, is managing over 10,968 pending clinical negligence cases, and holds estimated outstanding liabilities of €5.35 billion. Just 2% of resolved claims reached a court judgment, and 43% involved mediation.
You do not sue the individual doctor. The HSE is the legal defendant, and the SCA instructs its own panel of defence solicitors and medical experts. Between assessment and settlement, the sticking point is usually the SCA's own expert report, which can take 12 to 18 months in complex cases. For private hospital claims, the consultant's medical defence organisation (most commonly the Medical Protection Society or Medisec Ireland) manages the defence and instructs its own legal team separately. See our guide on claims against the HSE for the full process.
What "puts you on full proof" actually means
When you receive the formal Defence document, it will almost certainly contain the phrase "the defendant puts the plaintiff on full proof of his/her claim." Many claimants read this and wonder what it means. It is a blanket denial of every element of your case. It does not engage with the specifics of what happened. It does not admit any fact. It forces you to prove duty, breach, causation, and damages from scratch, as if the defendant has said nothing at all. This is a deliberate strategy, not a procedural formality. By putting you on full proof, the defence preserves every possible argument without committing to a specific position. Your solicitor expects this. It means your expert evidence must cover every element, because the defendant has declined to narrow the issues. The real picture of which defences are being actively pursued only becomes clear later, during discovery and the exchange of expert reports.
When the SCA admits breach but disputes everything else
A partial admission of liability does not mean your case is won. We regularly see the SCA concede breach of duty while vigorously contesting causation, the extent of injury, or the value of the claim. One detail that surprises clients: a letter admitting that treatment fell below the required standard can arrive alongside a defence that argues the patient's outcome would have been the same regardless. The real battle then shifts entirely to causation and quantum (compensation). According to the State Claims Agency Annual Report 2024, approximately 2% of clinical negligence claims involve catastrophic injury, such as cerebral palsy and severe brain injury, yet these claims account for over 50% of the total outstanding liability. This asymmetry shapes how the SCA allocates its defence resources. A routine soft-tissue claim receives a different level of scrutiny, expert investment, and negotiation approach than a multi-million euro catastrophic claim. Understanding where your case sits on that spectrum helps set realistic expectations about how aggressively the defence will contest each element.
How Is the Defence Medical Examination Used Against You?
The defendant's medical examination is not a neutral assessment of your injuries. It is a defence tool designed to find evidence that supports the defences described above. In almost every contested medical negligence claim, the defendant instructs their own independent medical expert to examine you. This examination serves multiple defence strategies simultaneously.
What the defendant's expert is looking for
The examination targets specific defence arguments. For the pre-existing condition defence, the expert checks whether your symptoms, range of motion, or imaging are consistent with a condition that predated the negligent treatment. For contributory negligence, they note whether your rehabilitation progress matches what would be expected if you had followed all medical advice. For the causation defence, they assess whether the current state of your injury is explained by the natural progression of disease rather than negligent treatment. For the exaggeration defence under Section 26, they compare your reported symptoms against clinical signs, looking for inconsistencies between what you describe and what they observe.
How to prepare without overstating or understating
Be accurate. Describe your symptoms on the day of the examination, not your worst day or your best day. Do not minimise to appear stoic and do not exaggerate to strengthen your case. Both approaches damage your credibility. Bring a list of medications you are taking and any aids you use, such as a crutch or brace. You are entitled to have someone accompany you to the examination, though they cannot intervene during the clinical assessment itself. Take a note of the examination's duration and what was tested immediately afterwards. Your solicitor may need this record if the defendant's report is challenged later.
↑ Back to topKey takeaway: the SCA's defence strategy is a system, not a single argument. The State Claims Agency raises multiple defences simultaneously, puts you on full proof even when liability seems conceded, commissions its own independent medical examination to challenge your symptoms, and deploys Section 26 to look for any inconsistency in your evidence. Approximately 2% of clinical negligence claims involve catastrophic injury, yet these account for over 50% of the SCA's outstanding liability, which means the SCA invests more resources in defending high-value claims. Your preparation must match that intensity: consistent and accurate reporting of your symptoms at every stage, a clear expert report addressing each defence the SCA is likely to raise, and a solicitor experienced enough to anticipate how the SCA approaches cases at your level. For an overview of what to expect at each stage, see our guide on settlement versus trial in medical negligence.
Quick-Reference: Common Defences and Counter-Strategies
| Defence | Legal Basis | How to Counter |
|---|---|---|
| General and approved practice | Dunne v NMH [1989], Morrissey v HSE [2020] | Dunne Principle 3: show the practice has inherent defects |
| Honest difference of opinion | Dunne Principle 5 | Show the choice was outside all reasonable options |
| Causation failure (but-for test) | Quinn v MWHB [2005], general tort principles | Expert evidence on staging, treatment options, material contribution |
| Contributory negligence | Section 34, Civil Liability Act 1961 | Document compliance. Reduces, does not defeat |
| Inherent risk or known complication | Dunne principles, Fitzpatrick v White [2007] | Link complication to specific clinical error, not statistical risk |
| Informed consent adequacy | Fitzpatrick v White [2007] IESC 51 | Prove risk was material. Prove you would not have consented |
| Statute of limitations | Statute of Limitations (Amendment) Act 1991 | Establish date of knowledge. Expert report timing is evidence |
| Delay or want of prosecution | Kirwan v Connors [2025], Primor [1996] | Keep the case moving. Instruct experts promptly |
| Open disclosure non-admission | Patient Safety Act 2023, s.10 | Use disclosure as investigative starting point, not proof |
| Guidelines are guidance only | Perez v Coombe [2025] | Expert must explain why departure fell below Dunne standard |
| Pre-existing condition | General tort principles | Compare trajectory with and without the breach |
| Exaggeration or misleading evidence | Section 26, Civil Liability and Courts Act 2004 | Be accurate in every medical report, affidavit, and examination |
Which Defences Will You Face by Claim Type?
The defences raised depend on the type of clinical error at the centre of your case. A delayed cancer diagnosis attracts different defence arguments to a retained surgical instrument. The table below maps the most commonly raised defences against the main claim types seen in Irish medical negligence litigation.
| Claim Type | Primary Defences Raised | Key Counter-Evidence Needed |
|---|---|---|
| Delayed or missed diagnosis (cancer, sepsis, stroke) | Causation failure ("outcome the same"), approved practice, contributory negligence (late presentation) | Staging data, survival statistics at earlier vs actual diagnosis date, GP attendance records |
| Surgical error (wrong site, retained instrument, nerve damage) | Inherent risk, honest difference of opinion, informed consent | Operative notes, consent form review, imaging showing mechanical error vs known complication |
| Birth injury (cerebral palsy, Erb's palsy, hypoxic brain injury) | Causation failure (injury occurred before labour), approved practice, pre-existing condition | CTG traces, partogram, timing of intervention vs NICE/RCOG escalation thresholds |
| Medication or dosage error | Contributory negligence (non-disclosure of allergies), causation failure, approved practice | Prescription records, allergy records, pharmacy dispensing logs |
| Failure to obtain informed consent | SCA's three consent arguments (would have proceeded, verbal disclosure, materiality) | Patient diary, witness evidence of expressed concerns, consent form compared to clinical notes |
| GP negligence (failure to refer, missed red flags) | Approved practice, causation failure (referral would not have changed outcome), guidelines not mandatory | ICGP clinical guidelines, referral pathway timelines, specialist opinion on earlier referral impact |
| Hospital-acquired infection | Inherent risk (expected infection rate), approved practice (infection control protocols followed) | Infection control audit records, HPSC surveillance data, documented breaks in protocol |
Who Bears the Burden of Proof for Each Defence?
For some defences, the claimant must prove their case survives the challenge. For others, the burden shifts to the defendant to prove the defence applies. Knowing which side carries the burden for each defence shapes how you allocate your evidence-gathering effort. The mapping below applies specifically to Irish medical negligence proceedings.
| Defence | Burden Falls On | Practical Implication |
|---|---|---|
| Approved practice (Dunne) | Defendant must prove the practice was general and approved | Claimant can then invoke Principle 3 (inherent defects) to rebut |
| Causation failure | Claimant must prove the breach caused the injury | Your expert report must address "but-for" causation directly |
| Contributory negligence | Defendant must prove the claimant's conduct contributed to harm | Keep records showing compliance with medical advice |
| Inherent risk | Defendant must prove the complication was a recognised risk, not error | Your expert links the outcome to a specific departure from care |
| Informed consent | Claimant must prove the risk was material and they would not have consented | Diary entries, witness evidence, and clinical notes are decisive |
| Statute of limitations | Defendant raises it, but claimant must prove date of knowledge was within time | Establish when you first knew negligence may have caused the injury |
| Exaggeration (Section 26) | Defendant must prove evidence was false or misleading and the claimant knew it | Be accurate in every medical appointment and legal document |
| Delay or want of prosecution | Defendant applies to court, but claimant must explain the delay | Keep your case file active and instruct experts without delay |
What If My Case Involves Multiple Defences?
The defences above are presented individually, but in practice they rarely appear alone. The SCA or a private insurer will raise several simultaneously, forcing your legal team to address each one with separate expert evidence and legal argument. The two anonymised scenarios below show how overlapping defences work in common Irish medical negligence claim patterns.
Scenario A: Delayed bowel cancer diagnosis at GP level
Facts: A patient in their 50s attended their GP three times over eight months with rectal bleeding. The GP attributed the symptoms to haemorrhoids without investigation. When a colonoscopy was eventually performed, stage III bowel cancer was diagnosed. The patient argues earlier investigation would have detected stage I disease, requiring less aggressive treatment and carrying a significantly better prognosis.
Defences raised:
(1) Approved practice: The GP's expert says attributing rectal bleeding to haemorrhoids in a patient with no red-flag history is within the range of general and approved practice. Counter: The claimant's expert identifies ICGP and NICE guidelines recommending urgent investigation of persistent rectal bleeding in patients over 50, and argues the GP's approach fell below the standard of a reasonably competent GP giving the matter due consideration (Dunne Principle 3).
(2) Causation failure: The defence argues that even with earlier diagnosis, the cancer may already have progressed beyond stage I, so the outcome would not have changed materially. Counter: An oncology expert provides staging data showing that at the date of the first consultation, the probability of stage I disease was approximately 65% based on tumour growth modelling. The claim is framed around the loss of the opportunity for less invasive treatment and improved survival odds.
(3) Contributory negligence: The GP's defence notes the patient cancelled one appointment and delayed returning for a follow-up blood test. Counter: The cancellation was rescheduled within two weeks. The delay in the blood test was three weeks. Neither materially changed the timeline compared to the GP's eight-month failure to investigate. The court would likely apportion minimal contributory negligence, if any.
Scenario B: Post-operative nerve damage following orthopaedic surgery
Facts: A patient underwent elective knee replacement at a public hospital. Following surgery, they developed foot drop caused by peroneal nerve damage. The patient argues the nerve was damaged during the procedure due to improper retractor placement.
Defences raised:
(1) Inherent risk: The hospital's expert states that peroneal nerve injury occurs in 0.3 to 1.3% of total knee replacements even with competent technique. It is a recognised complication. Counter: The claimant's expert reviews operative notes showing prolonged tourniquet time and retractor positioning inconsistent with the documented surgical approach, suggesting the nerve injury was caused by a specific technical error rather than the statistical risk materialising.
(2) Informed consent: The SCA argues the patient was warned of "nerve damage" as a risk on the consent form and would have proceeded regardless. Counter: The consent form lists "nerve damage" without specifying foot drop, permanent mobility impairment, or the specific risk to the peroneal nerve. The patient, who was an active hillwalker, produces a diary entry from before surgery recording concern about mobility and a conversation with a friend about whether to proceed. The claimant argues that specific disclosure of the peroneal nerve risk and its practical consequences (inability to walk on uneven ground) would have changed their decision.
(3) Pre-existing condition: The defence notes the patient had mild pre-existing neuropathy from diabetes. Counter: Pre-operative nerve conduction studies show the peroneal nerve was functioning within normal parameters before surgery. The foot drop was absent before the procedure and present immediately after. The pre-existing neuropathy did not affect the peroneal nerve.
These scenarios illustrate that every claim faces a specific combination of defences. Early identification of which defences your case is most vulnerable to allows your solicitor and expert to build targeted evidence for each one, rather than preparing generically. The questions below address the most common concerns people have once they understand what they are facing, starting with the distinction between a complaint and a legal claim.
Complaints vs Claims: Different Pathways
A complaint to the HSE through "Your Service, Your Say" or the Medical Council addresses professional standards, while a legal claim seeks compensation. The two processes are independent. You can pursue both, but a Medical Council finding does not automatically prove negligence in court. A HIQA investigation or a complaint to the Nursing and Midwifery Board (NMBI) can provide useful background, but none replaces the independent expert evidence required for a civil claim. Choosing the right pathway early avoids wasted time and missed deadlines.
↑ Back to topCommon Questions About Defences in Medical Negligence Claims
Can any single defence completely defeat my medical negligence claim?
Contributory negligence cannot defeat a claim. It reduces damages proportionally. However, causation failure and the statute of limitations can each completely defeat an otherwise valid claim. Causation failure means the breach did not cause the harm. A statute-barred claim means proceedings were issued too late.
The difference is critical: some defences reduce your award, while others end the case entirely. Knowing which category each defence falls into helps you prioritise evidence-gathering.
Why it matters: Early legal advice identifies which defences are most likely in your case.
Next step: How causation works in medical negligence
The hospital apologised. Does that prove negligence?
No. Under Section 10 of the Patient Safety Act 2023, an apology made during an open disclosure meeting is not admissible as evidence and does not constitute an admission of fault or liability in Ireland. The Act commenced on 26 September 2024 and applies to all HSE-funded and private health services.
Open disclosure is a starting point for your investigation. It tells you something went wrong. Proving negligence requires independent expert evidence establishing breach and causation under the Dunne principles.
Why it matters: Claimants who rely on an apology as proof are often surprised to discover it carries no legal weight.
Next step: How to prove medical negligence in Ireland
My doctor did not follow clinical guidelines. Is that automatic negligence?
Departure from a clinical guideline does not automatically prove negligence. The High Court in Perez v Coombe [2025] confirmed that guidelines such as IMEWS, RCOG, and NICE are "guidance tools only." The Dunne test remains the legal standard. Your expert must explain why the specific departure fell below what a competent practitioner would do, not simply point to the guideline.
Why it matters: Many families build their case around guideline breaches alone, and the defence dismantles it.
Next step: How breach of duty is established
I missed follow-up appointments. Will I lose my claim?
Missing appointments will not defeat your claim but may reduce your compensation. Contributory negligence under Section 34 of the Civil Liability Act 1961 is a partial defence. The court assesses what percentage of the harm is attributable to your own actions and reduces the award accordingly.
Keep records of all correspondence with your treatment team. Evidence of genuine barriers to attendance, such as symptoms, transport difficulties, or miscommunication, helps mitigate any reduction.
Why it matters: Defendants routinely allege contributory negligence to reduce damages.
Next step: Medical negligence compensation in Ireland
Can my case be thrown out for taking too long?
Yes. Following the Supreme Court's revised framework in Kirwan v Connors, delays of two or more years may result in dismissal. Delays of four or more years should be dismissed unless the plaintiff provides a convincing explanation. Delays of five or more years carry a strong presumption of dismissal.
The court also considers whether proceedings were served with a supportive expert report. Serving without one may lead to dismissal for abuse of process.
Why it matters: Courts are less tolerant of delay than at any previous point in Irish legal history.
Next step: Why expert medical evidence is essential
The hospital says I would have had the same outcome anyway. Can I still claim?
You may still have a claim, but causation is the element you must prove. The but-for test asks whether your injury would have occurred regardless of the negligence. Expert evidence comparing the likely outcome with and without proper care is critical. Where negligence materially contributed to a worse outcome, even if it did not solely cause it, there may still be a route to recovery under the material contribution principle.
Why it matters: Causation defeats more valid claims than any other defence in Irish medical negligence litigation.
Next step: Causation in medical negligence claims
Who defends the case, the doctor or the hospital?
For public hospitals, the State Claims Agency defends the claim on behalf of the HSE under the Clinical Indemnity Scheme. The individual doctor is not typically a party to the proceedings. For private hospitals and consultants, the Medical Protection Society, Medisec Ireland, or the hospital's own insurer manages the defence.
Why it matters: The SCA has substantial resources and a structured approach to defending claims.
Next step: Claims against the HSE
Does UK medical negligence law apply in Ireland?
No. Ireland uses the Dunne test, not the English Bolam/Bolitho test. The limitation period is two years in Ireland versus three years in England and Wales. Ireland applies the Fitzpatrick v White consent standard, not the Montgomery ruling. The Judicial Council's Personal Injuries Guidelines govern Irish awards, not the Judicial College Guidelines. UK-based online guides do not reflect Irish law.
Why it matters: Online sources frequently conflate Irish and UK rules.
Legal Sources Cited in This Guide
All sources are Irish unless otherwise stated. Last checked March 2026.
Case Law
- Dunne v National Maternity Hospital [1989] IR 91 (Supreme Court). Established the six Dunne principles for assessing medical negligence in Ireland. Reaffirmed in Morrissey v HSE [2020] IESC 6. Irish Legal News analysis
- Fitzpatrick v White [2007] IESC 51 (Supreme Court). Established the patient-centred test for informed consent. BAILII judgment text
- Perez v Coombe [2025] (High Court). Confirmed clinical guidelines are guidance, not mandatory legal rules. Mason Hayes Curran analysis
- Kirwan v Connors [2025] IESC 21 (Supreme Court). Revised the Primor delay-dismissal framework with tiered thresholds at 2, 4, and 5 years. Courts Service judgment
- Philp v Ryan [2004] IESC 105 (Supreme Court). Allowed proportional damages for loss of life expectancy in delayed cancer diagnosis.
- Quinn v Mid Western Health Board [2005] (Supreme Court). Required full but-for proof of causation.
- O'Sullivan v Ireland [2019] IESC 33 (Supreme Court). Addressed date of knowledge for limitation purposes. Courts Service judgment
Legislation
- Civil Liability Act 1961, Section 34. Contributory negligence and apportionment of fault. Law Reform Commission Revised Acts
- Statute of Limitations (Amendment) Act 1991. Two-year limitation period for personal injury claims. Law Reform Commission Revised Acts
- Civil Liability and Courts Act 2004, Section 26. Mandatory dismissal for materially false or misleading evidence. Irish Statute Book
- Patient Safety (Notifiable Incidents and Open Disclosure) Act 2023. Commenced 26 September 2024. Mandatory open disclosure; Section 10 non-admissibility protection. Irish Statute Book | Oireachtas bill history
Reports and Guidelines
- State Claims Agency Annual Report 2024. Clinical care damages, case volumes, outstanding liabilities, and mediation data. NTMA
- Judicial Council Personal Injuries Guidelines. Compensation bands for general damages in Irish personal injury claims. Judicial Council
Complaints Pathways
- Making a complaint about the health service. Citizens Information
- HSE "Your Service, Your Say" complaints process. HSE
- Making a complaint to the Medical Council. Medical Council of Ireland
Related internal guides: Medical negligence claims process • Proving causation • Breach of duty explained • Time limits • Consent failures • Compensation guide • No Win No Fee
This page provides general information on common defences in Irish medical negligence claims. It is not legal advice and does not replace tailored guidance on your own situation. Every case depends on its own facts, injuries, and evidence. If you believe you have experienced medical negligence, seek advice from a solicitor experienced in Irish medical negligence law.
Gary Matthews Solicitors
Medical negligence solicitors, Dublin
We help people every day of the week (weekends and bank holidays included) that have either been injured or harmed as a result of an accident or have suffered from negligence or malpractice.
Contact us at our Dublin office to get started with your claim today
