In clinical negligence cases it will inevitably be important to identify the appropriate defendant. The NHS is fragmented into a number of Health Authorities, however in the vast majority of cases the body responsible to meet a claim for clinical negligence, and therefore the appropriate defendant, will be an individual NHS Trust and/or a particular GP’s practice.

The courts approach the issue of breach of duty in cases of clinical negligence by reference to the Bolam test, i.e. the test formulated by McNair J. in his direction to the jury in Bolam v Friern Hospital Management Committee [1957] 1 W.L.R. 582. The effect of the Bolam test, as interpreted by the House of Lords in Bolitho (Deceased) v City and Hackney HA [1998] A.C. 232, HL is that the defendant must live up to the standard of the ordinary skilled man exercising and professing to have that special skill, and should not be found to be negligent if he has acted in accordance with a practice accepted as proper by a responsible body of medical men skilled in the particular art. The existence of the practice is not of itself determinative of the question of negligence. The court has to subject the evidence from medical expert witnesses to scrutiny and analysis in order to decide whether it establishes that the practice or decision of the defendant was reasonable. The issue of reasonableness is ultimately for the court and not for the expert witnesses although the issue must be properly put to the expert witnesses for their comment (see Burne v A [2006] EWCA Civ 24).

In a clinical negligence action involving an allegedly negligent failure to take a particular step, causation is conventionally proved by showing that if the defendant had not been negligent (and had taken the relevant step) the claimant would, on a balance of probabilities, have avoided his ultimate injury. However, in Bolitho [1998] A.C. 232, HL, an alternative approach was advanced. In that case the claimant argued that the defendant’s failure to attend when called was negligent (a point accepted by the defendant) and that if the relevant doctor had attended she would and/or should have intubated him (this was accepted as being the only step which could have avoided his ultimate respiratory arrest). The doctor’s evidence was that she would not have intubated him (because she lacked the necessary expertise) and the defendant’s evidence was that the failure to intubate would not have been negligent. Accordingly, in Bolitho the argument as to causation was that the claimant should succeed if the court were to find that the failure to intubate would have been negligent notwithstanding the trial judge’s finding that the doctor would not have intubated. This necessitated the unconventional step of applying the Bolam test not only to the question of breach of duty (i.e. should the doctor have attended) but also to the question of causation (i.e. should she have intubated if she attended). The House of Lords accepted that this argument was available in principle but found on the facts that a failure to intubate would not have been negligent.

It is not known precisely how the Bolitho argument as to causation would apply where the party who it is alleged ought to have taken steps to avoid the claimant’s injury is someone other than the defendant, for example, where the clinical negligence claim is against a GP for failure to refer a patient to a specialist and the enquiry for causation is whether or not the specialist would and/or should have diagnosed the claimant’s condition. However, in Gouldsmith v Mid-Staffordshire General Hospitals NHS Trust [2007] EWCA Civ 397, the claimant was able to demonstrate a negligent failure to refer. The expert evidence was that if the claimant had been referred, she would most likely have been operated on, preventing the injuries sustained, but that a decision not to operate would not have been negligent. A majority of the Court of Appeal held that in these circumstances, there was no need for the claimant to prove that “the hospital of reference would have been bound (in the Bolam sense) to have operated”. The claimant having shown that most specialists would have been likely to operate on her, the evidential burden of proof was thereby transferred to the defendant to show that “the reference would be likely to have been to a particular specialist who would not have operated”. See also Wright (A Child) v Cambridge Medical Group (A Partnership) [2011] EWCA Civ 669.

The Court of Appeal has clearly stated that if Bolitho causation arguments are to be run, i.e. causation is to be argued in the alternative, then it should be expressly pleaded so as the defendant is able to formulate his defence.

Causation in cases of delay in providing treatment or diagnosis must be approached in accordance with the guidance from the courts as set out in Tahir v Haringey Health Authority [1998] Lloyd’s Rep. Med. 104, namely that the evidence must establish an identifiable injury caused by the negligence and that it is insufficient merely to plead, or prove, that the alleged negligence “made matters worse”. Further guidance on causation in cases of delay was provided by the House of Lords in Hotson v East Berkshire Health Authority [1987] A.C. 750 where it was held, on the facts of that case, that damages were not recoverable for loss of a chance of full recovery, as in that particular case, the evidence was that as at the time of the negligence the claimant did not have a chance of recovery as such. Rather, the evidence established that as at that time he would either have recovered, or not, and the difficulty was in ascertaining which category he would have been in. This principle that there can be no damages for loss of a chance of achieving a better outcome or avoiding a particular injury was confirmed by the House of Lords in Gregg v Scott [2005] UKHL 2.

In a medical negligence case, the Claimant has to show, on the balance of probabilities, both a “breach of duty” and that the breach of duty “caused” loss.

Thus, even if a claimant can establish “breach of  duty” he/she may still have very complicated causation issues to address on the medical evidence. Alternatively, even if a claimant can establish medical and legal causation, he/she may struggle to establish  breach of duty. Establishing  breach of  duty can often be very difficult because of the availability of the “Bolam defence”. In broad terms, professionals can avoid liability if they can show that others would have done the same thing.