A v National Blood Authority – Case Summary

A v National Blood Authority

High Court

Citations: [2001] 3 All ER 289; [2001] Lloyd’s Rep Med 187; (2001) 60 BMLR 1; [2001] CLY 2933.


The claimants were patients who were infected with hepatitis C during blood transfusions performed in the late 1980s. It was not broadly known by the public at the time that there was any risk of infection by blood transfusions. The claimants sought damages against the National Blood Authority under the Consumer Protection Act 1987 and Council Directive 85/374.

The National Blood Authority argued that the blood was not defective, so they were not liable. They also argued that even if the blood was defective, the defence under section 4(1)(e) of the Act (and its equivalent under Article 7(3) of the Directive) applied. They accepted that medical professionals at the time knew there was a risk that blood supplies may be tainted with hepatitis C. However, they argued that there was no mechanism for screening blood for the disease. This meant that the harm was unavoidable.

  1. What factors are relevant to whether a product ‘defective’ under the Consumer Protection Act 1987?
  2. If a risk is known about but unavoidable, does this fulfil the conditions of the defence under section 4(1)(e) of the Consumer Protection Act 1987?

The High Court held in favour of the claimants. It was legitimate for consumers to expect that the blood they were provided was safe. The tainted blood was therefore defective. The section 4(1)(e) defence was inapplicable to the facts.

This Case is Authority For…

The level of safety which consumers are entitled to expect of a product may be the same as what consumers actually expect, or it may be higher or lower. When determining whether a product is defective, the following factors are irrelevant:

  • The avoidability of the risk;
  • The cost and difficulty of avoiding the risk.

In addition to the factors mentioned in section 3 of the statute, the safety of comparable products on the market is relevant to whether there is a defect.

For the purposes of section 4(1)(e), if the risk of harm is known about, it is irrelevant that current scientific/technical knowledge is unavoidable. This is true both in cases where the defendant cannot eliminate the risk and in cases where the defendant cannot identify which products pose the risk. Known but unavoidable risks do not qualify for the defence.


The High Court stated that to determine if a product is defective, it is helpful to distinguish between ‘standard’ and ‘non-standard’ products. Products which are standard do not deviate from the intended design – the harmful characteristic is a feature of the product. A product which is non-standard deviated from the intended design in some harmful manner.

Standard products are only defective if a reasonable consumer would consider it unsafe, bearing in mind all foreseeable ways the product could be used. The social utility of the harm-causing feature can be relevant, so long as the public is fully-informed about it and accepts it. An example of this given by the High Court was knives being sharp.

Non-standard products are presumed to be defective unless the risk of non-conformity is well-known and socially accepted. An example given by the High Court was the risk that birth control may not be 100% effective. Social utility is irrelevant to whether or note a non-standard product is defective.

This aspect of the case was disapproved of by the High Court in Wilkes v DePuy International Ltd [2016] EHWC 3096.