The duty of the courts is to interpret the words
Lord Simonds in Magor and St. Mellons R.D.C. v Newport Corporation  A.C. 189 at 191
In the light of this statement, examine the rules of statutory interpretation and provide an analysis of the extent of the power of judges when interpreting statutes.
As Lord Simonds states above, it is the judge’s duty to interpret legislation that is passed by Parliament; Acts can be incomplete or ambiguous so it is not always as straightforward as one might think. Statutory Interpretation is the method of interpreting these Acts. Lord Hailsham said that probably as many as nine out of ten cases heard on appeal by the Court of Appeal and the House of Lords turn upon or involve the meaning of words contained in statutes or secondary legislation.  I will take each of the rules of interpretation and consider how each one works, providing examples of cases where they have been applied. I will take quotes from the relevant Lords judgments to consider where opinion on each rule lies and the pros and cons of each. I will also analyse the critique of relevant scholars like Ronald Dworkin, Sir Rupert Cross and Griffith.
Interpretation is not left solely up to the judges own will; Parliament passed The Interpretation Act in 1978 to provide assistance, for example ‘words importing the masculine gender include the feminine’ and ‘words in the singular include the plural and words in the plural include the singular’  .
There are three main rules of statutory interpretation – the literal rule, the golden rule and the mischief rule. The literal rule ‘gives all the words in a stature their ordinary and natural meaning, on the principle that the best way to interpret the will of Parliament is to follow the literal meaning of the words they have used.’  The use of the literal approach has created some absurd rulings, like in Whitley v Chappell  . In this case the law stated that it was illegal to impersonate ‘any person entitled to vote’; the defendant impersonated a dead person, who was evidently not ‘entitled to vote’. Consequently the defendant was acquitted using the literal meaning of the Act.
In London and North Eastern Railway Company v Berriman  it was held that a woman was not entitled to compensation for her husband’s death. He had been performing maintenance on the railway track when he was killed, but not specifically ‘relaying or repairing’ the tracks as the relevant Act required. Lord Reid said in I. R. C. v. Hinchy  , "We can only take the intention of Parliament from the words which they have used in the Act"; this statement shows that at the time the Lords were reluctant to depart from the literal rule. Expanding slightly on this, Lord Reid in Jones v DPP  set out the limitations to which judges could interpret statutes. He said "It is a cardinal principle in all statutes that you may not attach to a statutory provision a meaning that the words of that provision cannot reasonably bear. If they are capable of more than one meaning, then you can choose between those meanings, but beyond that you must not go."
The literal rule does have its benefits, because it ‘respects parliamentary sovereignty, giving the courts a restricted role and leaving law-making to those elected for the job  ’. This in turn means that judges don’t have a lot of power in interpretation, if the literalist way were to be the adopted one. There are great flaws to the literal rule though, for instance ‘those who apply the literal approach often talk of using the ‘dictionary meaning’ of the words in question, but dictionaries provide a number of alternative meanings’.  The literal method only creates certainty if it is constantly adhered to, but as Glanville Williams noted; ‘The doctrine of literalness can never be applied successfully to general words. For they always include something more than the scope and object of the statute required and so it leads to ridiculous results’.  Lord Denning later said "We no longer construe Acts according to their literal meaning. We construe them according to their object and intent". This marks a significant shift away from the more traditional literal approach which ‘assumes unattainable perfection in draftmanship.’ 
The golden rule is an adaptation of the literal rule which can be applied when the literal rule would provide an absurd result. In Grey v. Pearson  , Lord Wensleydale set out that "the ordinary sense of the words is to be adhered to, unless that would lead to some absurdity… when the ordinary sense may be modified to avoid the absurdity but no further." This established the golden rule as a recognised interpretation method. In R v. Allen  it was held that ‘married’ could be read as ‘having gone through a ceremony of marriage’ as it is impossible to be ‘married’ twice. Using the literal approach would mean that they had not broken the law, making the Act worthless, so the golden rule was used to convict the defendant. Professor Zander says how "The golden rule is... little more than a safety-valve to permit the courts to escape from some of the more unpalatable effects of the literal rule. It cannot be regarded as a sound basis for judicial decision-making  ’. The golden rule allows the judges more power as it gives them the opportunity to part from the literal meaning of the legislation.
The next rule is the mischief rule, which was established in Heydon’s Case  ; it must be asked (a) what the law was before the statute, (b) what was the ‘mischief’ that the common law didn’t provide, (c) what remedy was Parliament trying to provide and (d) the reason for the remedy. In Smith v Hughes  , a prostitute solicited passers by from a first floor window, not ‘in a street or public place’ which the Street Offences Act 1959 legislated against. The mischief Parliament intended to remedy was soliciting people on the street, ‘even though the prostitute was not in the street herself, the Act should be interpreted to include this activity’  using the mischief rule.
In Royal College of Nursing v DHSS  the relevant statute made it only lawful for abortions to be carried out by ‘registered medical practitioners’, which nurses were not. It was Parliaments intention to ensure safe abortions, so it was held that nurses’ involvement was not unlawful. ‘It was a controversial decision, with Lords Wilberforce and Edmund Davies claiming that the House was not interpreting legislation but rewriting it.’  This claim of altering the law was not a new one, in 1840 Lord Brougham had said “if we depart from the plain and obvious meaning on account of such views, we in truth do not construe the Act but alter it"  . It shows the shift in power over time, placing more power in the judge’s hands.
At their disposal the judges have secondary aids to interpretation; these include internal aids which are found within the statute, like the short title, the long title, the preamble etc. Also there are extrinsic aids which are sources separate from the statute. The Human Rights Act 1998 is probably the most notable as it incorporated the European Convention on Human Rights (ECHR) into UK law. It requires national parliaments to interpret Acts so they are compatible the Convention. ‘This is quite clearly an exception to the literal rule... it is quite possible that a literal interpretation of a provision will conflict with a right or freedom contained within the ECHR and yet s 3 (1) states that in those circumstances the literal rule should not be followed.’  ‘The Human Rights Act 1998 is likely to prompt a shift towards more purposive interpretation, as the courts weigh up important issues concerning rights of the individual against the state, and take into account the judgments of the European Court of Human Rights, which itself takes a purposive approach to interpretation’. 
The Purposive approach is similar to the mischief rule but places emphasis on the will of Parliament instead of what the previous common law remedy was. Hansard is a particularly useful aid when using the purposive approach; it was first used officially in Pepper v Hart  . Law Commission Reports have been available to aid interpretation since Davis v. Johnson  , where it was said that "the report may be used to identify the mischief the legislation is intended to remedy but not to construe the enacting words". Dictionary definitions can also be used but this is more useful to the literal rule.
The concept of Stare Decisis, or let the previous decision stand, creates precedent; this should mean that there’s certainty in the law because it means the courts are bound by previous decisions. However, statutory interpretation takes away a lot of the certainty because there are different rules which create very different outcomes, particularly since the emergence of the golden and mischief rules. It is up to the judge to decide which rule to apply and what they might see as a fair and just result others may not, which forms an argument against the golden rule.
Sir Rupert Cross suggests the courts take a ‘contextual approach’ and the Noscitur a sociis rule, ‘where a word draws meaning from the other words around it’  . This is merely an adaptation of the golden rule. It takes the ordinary meaning before considering others if it creates an absurd result. The distinguishing feature is that it places more emphasis on the context of the Act. Cross’s theory is more literal, as it does not allow the judges to look beyond the Act itself; this fits in with the Lords views that they should not venture too far. "It is a cardinal principle in all statutes that you may not attach to a statutory provision a meaning that the words of that provision cannot reasonably bear. If they are capable of more than one meaning, then you can choose between those meanings, but beyond that you must not go"  Lord Reid.
Dworkin’s theory involves the judges travelling outside of the case itself, and developing ‘a theory about how the particular measure they are dealing with fits with the rest of the law as a whole’  . This is to make the judiciary more coherent and so it has a clear direction. If however, the outcome is absurd the judges can depart from the rest of the law. This is of course true because judges do not make rash decisions, they follow precedent and distinguish past cases.
‘Griffith claims that, where there is ambiguity, the judiciary chooses the interpretation that best suits their view of policy.’  From Bromley London Borough Council v Greater London Council  it can be seen ‘that an apparently unlimited discretionary power will not in itself prevent the courts from finding grounds for intervention, nor from declaring, where they think it appropriate, that the exercise of such discretion might be ultra vires.’  The judges did ‘not consider themselves bound to respect decisions made in fulfillment of an elected body’s manifesto’  . It is plain to see from this case that the judges interfered ‘with the role of elected authorities’  and it is likely that they will be influenced by their policy stance when interpreting the law.
As with most areas of law, there have been calls for reform on the subject of statutory interpretation. ‘The Law Commission examined the interpretation of statutes in 1967 and had ‘little hesitation in suggesting that this is a field not suitable for codification’’.  It was suggested a ‘more liberal use should be made of external and intrinsic aids’  and ‘in the event of ambiguity, the construction which best promoted the ‘general legislative purpose’ should be adopted.’  The Commission ‘urged adoption of the ‘mischief’ or ‘purposive approach to statutory interpretation but did not favor recourse to parliamentary debates... lack of clarity in such debates... the value to be derived from parliamentary debates was likely to be outweighed by the burden of consulting them.’ 
The Hansard Society said ‘The possibilities for confusion... and for time wasting argument and counter-argument in the court... are endless’,  regarding the use of considering parliamentary debate. Through these reports it can be seen that the consensus was in favor of a purposive approach, but specifically opposed the use of Hansard. The Renton Committee among other suggestions argued for less detail in legislation and ‘it highlighted examples of convoluted drafting in British statutes and recommended improving the explanatory notes that accompany statutes.’ 
Concluding the rules of interpretation, it can be noted that they are not too dissimilar from each other. The Law Commission said in 1979 that ‘the golden rule turns out to be a less explicit form of the mischief rule’  . The mischief rule is also similar to the purposive approach because the judge considers factors external to the case. Statutory interpretation started off very narrow and has evolved through the golden and mischief rules which have gradually worked towards a more purposive approach. The literal rule is now outdated, its biggest critic was Lord Denning. The Law Commission said of the literal rule, ‘it ignores the limitations of language’  . Earlier judges were reluctant to act ultra vires, but support for a purposive approach gained pace in the 1960’s and 70’s. Lord Simonds described ‘filling in the gaps’ as ‘a naked usurpation of the judicial function, under the guise of interpretation... If a gap is disclosed, the remedy lies in an amending Act’  . To analyse the extent of judges power it must be said the courts have been allowed more power when interpreting statutes, particularly in the last fifty years, but it would seem they have assumed this power unwillingly, bar perhaps Lord Denning.
Word Count: 2,207
Table of cases
Whitley v Chappell  4 LRQB 147
London and North Eastern Railway Company v Berriman  HL
R. C. v. Hinchy  AC 748
Grey v. Pearson  6 HL Cas 1
R v. Allen  LR 1 CCR 367
Jones v DPP  AC 635, HL
Smith v Hughes  QBD
Gwynne v Burnell  6 Bing NC
Royal College of Nursing v DHSS  HL
Pepper v Hart  HL
Davis v. Johnson  AC 264
Bromley London Borough Council v Greater London Council