In Boston Scientific Medizintechnik GmbH v AOK Sachsen-Anhalt and Another the European Court of Justice gave a purposive interpretation to the definition of “defect” for the purposes of the EC Product Liability Directive 85/374/EEC in the context of medical devices.


In Boston Scientific the European Court of Justice considered a request for a preliminary ruling in two joined cases from the German Federal Court of Justice regarding the interpretation of EC Directive 85/374/EEC concerning liability for defective products (the “Directive”).

The Directive, in so far as relevant to this case, provides as follows:

Article 1
The producer shall be liable for damage caused by a defect in his product.

Article 6(1)
A product is defective when it does not provide the safety which a person is entitled to expect, taking all circumstances into account, including:

(a) the presentation of the product;
(b) the use to which it could reasonably be expected that the product would be put;
(c) the time when the product was put into circulation.

Article 9
For the purpose of Article 1, ‘damage’ means:

(a) damage caused by death or by personal injuries.

In the first case, the Defendant had produced a series of pacemakers which, it discovered, might suffer from gradual degradation which could lead to premature battery depletion and loss of pacing output without warning. The Defendant suggested doctors consider replacing the affected pacemakers.

In the second case, the Defendant discovered that the functioning of a series of defibrillators it had produced might be affected by a defect which could limit their therapeutic efficacy. The Defendant suggested the potentially faulty switch contained within the defibrillators be deactivated. The order of the referring court made clear the deactivation of the switch did not constitute a danger to a patient’s life or physical well-being.

The Court was asked to consider two preliminary issues:

  1. Whether Article 6(1) of the Directive is to be interpreted as meaning that a product in the form of a medical device implanted in the human body is already defective if products in the same product series have a significantly increased risk of failure but a defect has not been detected in the particular device in question.
  2. If so, whether the costs of removing and replacing the product constitute “damage caused by…personal injury” for the purposes of the Directive?


In relation to the first preliminary issue, the Court held that the exercise of considering what level of safety a person is entitled to expect should be carried out with regard to the reasonable expectations of the public at large. The safety that the public at large is entitled to expect must be assessed “by taking into account, inter alia, the intended purpose, the objective characteristics and properties of the product in question and the specific requirements of the group of users for whom the product is intended.”

In light of the function of medical devices and the vulnerability of patients who use them, the safety expected of those devices is particularly high. Such expectations are compounded by the abnormal potential for damage presented by such devices.

The Court therefore ruled that, where medical products such a pacemakers and defibrillators are part of a production series which has a potential defect, it is possible to classify all products in that series as defective, without the need to demonstrate that the product in question is in fact defective. Such an interpretation was said by the Court to be consistent with the objective of the Directive to achieve a fair apportionment of risks between producer and consumer.

In relation to the second preliminary issue, the Court ruled that the costs relating to an operation to remove and replace a defective product constitute damage under Article 9.


The Directive and, in the UK, the Consumer Protection Act 1987 (the “Act”) impose a regime of strict liability on producers, meaning that a claimant does not need to demonstrate fault on the part of the producer. However, it is incumbent on the claimant to establish that: (1) the product was defective; and (2) the defect caused damage.

Previous UK cases have interpreted the Act as requiring the claimant to show, with some precision, the nature of the defect. In Richardson v LRC Products Ltd [2000] Lloyd’s Rep Med 280, Mr Justice Kennedy held in a case involving a fractured condom that the mere existence of a fracture was, without more, not probative of a defect. In Foster v Biosil [2000] 59 BMLR 178, Cherie Booth QC, sitting as a Recorder in the County Court, found herself bound by Richardson to hold that a claimant in a case involving allegedly defective breast implants must show precisely what was the defect.

However, it appears the tide is changing. In the joint appeals of Ide v ATB Sales Ltd; and Lexus Financial Services (t/a Toyota Financial Services (UK) plc) v Russell [2008] EWCA Civ 424, there was an issue as to the approach the judge should take in determining proof of causation where alternative mechanisms of causation were put to the court. In the course of his judgment, Lord Justice Thomas held that in determining under the Act whether a loss has been caused in anyway by a defect, the role of the court is simply to determine whether the loss was caused by the defect, and not by some other cause. However, the process of reasoning may involve an explanation of how the defect was caused.

More recently in Love v Halfords Limited [2014] EWHC 1057, the Claimant suffered injuries when falling from his bike, which he bought from the Defendant. It was the Claimant’s case that his fall was caused by a defect in the bike’s steerer tube, present at the time of purchase, which caused it to fracture. The Defendant’s case was that, after the sale of the bike, but prior to the accident, something happened to bend the steerer tube and somebody had subsequently attempted to straighten it.

In considering the legal position Sir Colin Mackay, sitting as a judge in the High Court, referred to Ide v ATB Sales Ltd and stated: “Thomas LJ added that it was not necessary for the judge to…make any finding as to why the part had failed. That is the effect, as I understand it, of the wording of the Act which requires only the proof of a causative defect…

On the facts the judge found that there must have been “…a prior event in the course of which the [steerer] tube was damaged…” although the Defendant was unable to say with any specificity how the defect occurred. The judge concluded from the evidence that the bike had been involved in an accident prior to that which caused the Claimant’s injuries.

Similarly, in Hufford v Samsung Electronics (UK) Limited [2014] EWHC 2956 a claim was brought under the Act in relation to damage allegedly suffered as a result of a fire involving a fridge freezer manufactured by the Defendant. The essence of the Claimant’s case was that the fire originated inside the fridge freezer in the normal course of use and its safety was therefore “not such as persons generally are entitled to expect“, meaning that it was defective under the Act. The Defendant’s case was that the fire originated outside the fridge freezer.

When setting out his analysis of the relevant legal principles, His Honour Judge David Grant rejected the Defendant’s submission that “the claimant has to prove with a reasonable degree of specificity the respect in which the product was defective” and held that “…under the Act, a claimant does not have to specify or identify with accuracy or precision the defect in the product he seeks to establish, and thus prove. It is enough for a claimant to prove the existence of a defect in broad or general terms…” Ultimately, however, the judge found on the facts that the Claimant had failed to establish the fridge freezer was defective.

Boston Scientific appears to have lowered the level of proof required to establish the existence of a defect in a product which is one of a group or series. However, the decision seems to be confined to medical products which have an abnormal potential for damage and in circumstances where patients are entitled to expect a high degree of safety. It will be interesting to see how the English courts seek to apply the European Court of Justice’s reasoning to future cases in relation to proof of a product defect.


Tony Dempster
Tony Dempster
Partner, London
+44 20 7466 2340
Nick Case
Nick Case
Associate, London
+44 20 7466 2639