The House of Lords, the highest court in the UK, changed the law last week when it allowed the victim of the so-called Lotto rapist to bring a civil claim 15 years after the attack.

To make that change, the law lords had to overrule a decision that the court had made in 1993 barring the victims of a sexual attack from bringing a claim more than six years after the event. In order to allow the victim, Mrs A, to proceed, the law lords had to rule that the law was wrong. But how can they just change the law like that?

On one hand, you want a legal system under which, when the top court decides what the law is on something, it sticks to it. That way you get certainty, not flip-flopping in the lower courts. But on the other hand, the law should be organic and grow with society, not fossilised and inert.

What the House of Lords did last week was to use a special rule known as “the 1966 Practice Statement” that enables it to depart from an earlier ruling of the law lords if the circumstances demand it.

The House of Lords used to be bound by its own previous decisions. Once it declared what the law was, it was sometimes stuck that way for over a century. The justification was that decisions of the highest court in the land should be final. However, a special statement of new principle was given by Lord Gardiner, the Lord Chancellor, in 1966.

He said that in general the use of precedent is “an indispensable foundation” on which to decide the law. He noted, though, that “too rigid adherence to precedent” can cause injustice in a case and unduly restrict “the proper development of the law”. He argued that while treating their former decisions as normally binding, the Lords should depart from a previous decision “when it appears right to do so”.

Since 1966, the law lords have used this power sparingly. It won’t overrule its own previous decision just because some of today’s law lords disagree with the legal analysis of their predecessors. A “material change” of social circumstances must usually be shown.

In Herrington v British Railway Board (1972), the House of Lords overruled its earlier version of the law as put in Addy and Sons v Dumbreck (1929). In the 1929 case, the law lords decided that an occupier of premises was only liable for the injury to a trespassing child if that child was hurt intentionally or recklessly. In the 1972 decision, the Lords changed the law in line with the way social and physical conditions had changed since 1929. They said that even a trespasser was entitled to some small degree of care, which they expressed as a test of “common humanity”. They said that with the increase in population and more people living in cities, there was less playing space for children and so a greater temptation to trespass. Occupiers, therefore, should owe some duty to guard tempting but perilous premises — not so as they would have to pay out huge sums to all children injured while doing dangerous things they knew were wrong, but to manage premises with an eye to avoiding predictable death or injury to “innocent” trespassers.

On the whole, people are happy with the idea that the law can be modernised by the most senior judges (as opposed to elected members of a legislature) but when judges will change the law is unpredictable. And it can be seen as problematic if the judiciary is an unpredictable law-giver. In some cases, such as the recent one on sexual assault and damages, the lords have boldly made new law in line with changing social expectations. In R v R (1992), the House of Lords confidently saw fit to abolish the then 256 year-old rule against a charge of marital rape. Since then it has been possible for a man to be charged with raping his wife. In other cases, though, the law lords have declined to change the law, saying that that sort of thing should be left to parliament. In 1995 it refused to change the law regarding the criminal liability of 10-14 year olds (to make it easier to prosecute them); Parliament did so three years later.

The fact that the House of Lords can now change its mind when it wants to isn’t nearly as bad as when, before 1966, it couldn’t change its mind at all. As Lord Atkin observed in 1933: “Finality is a good thing, but justice is a better”.

Professor Gary Slapper is Director of the Centre for Law at The Open University

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