Traditionally judges had to rely solely on the precise wording of statutes when applying the law to factual cases. Parliamentary intention could not be scrutinised through examination of its debates, and external bodies of expertise in particular areas were not solicited for their general observations or comments. Over the course of the previous decade there has been a movement towards the acceptance of external aids to assist judges in interpreting statutes.
This began with the crucial case of Pepper (Inspector of Taxes) v.Hart  A. C. 593. Altough the law is not entirely clear to what extent external aids are permitted in which circumstances, Lord Browne-Wilkinson did attempt to restrict its use in his judgement in Pepper, to where the "legislation is ambiguous or obscure, or leads to an absurdity" (at p640). In the case under consideration, Regina v. Bournewood Community and Mental Health N. H. S. Trust, ex Parte L.  1 A. C. 458, his logic has certainly been applied and the assistance the courts gained from external sources was extensive.
These sources included the use of Hansard, the white paper of the Mental Health Act 1984, commissions, most notably the Mental Health Act Commission, and input from the Secretary of State for Health and the Registered Nursing Home Association. Lord Woolf stated at the Court of Appeal that "the circumstances in which the mentally ill may be detained are very carefully prescribed by statute" (at p. 470). However he went on to use external aids to assist him decipher the statute, which is an indication that the statute was possibly not as clear as he intimated.
Alternatively he may simply have been using secondary academic texts, as is common in the French legal system, and the Review of the Mental Health Act 1959 (1978) to strengthen his interpretation of the act. Lord Woolf in the Court of Appeal, looked at a specialist mental health textbook to define 'detained' in professional terms but was uneasy about applying this interpretation legally. The use of external factors here could therefore appear to be insignificant. However, only Lord Woolf knows the extent to which this did actually influence his decision that L was unlawfully detained.
How far any judges personal values sway their decisions is unknown, as they would not wish this to be apparent and it is beneficial to them to find external factors which support their privately held views. The House of Lords went further in their use of external material, including hansard, input from a number of bodies and commissions including the Mental Health Act commission and the Registered Nursing Home Association. More controversially, the Secretary of State for Health was able to contribute. This goes against the traditional principle that parliament writes statutes for the judges to interpret and apply to cases as they arise.
However, the use of such secondary aids, particularly parliamentary documentation, does help judges to apply statutes in the way parliament intended them to be, and takes an amount of discretionary power away from judges. In a democratic system the movement that began with Pepper v Hart puts the law making power more firmly in the hands of elected representatives. b) Many varying approaches can be taken by judges to reach their decisions, whether the case is clear, difficult or hard. These approaches are that of textual formalist, purposive formalist, and weak or strong realist.
Statutes can be applied using one of three rules, the literal, golden, or mischief rule. As the Bournewood case illustrates, different approaches to interpretation can provide the same result. It is not always clear which approach or rule is being adopted, and judges may even attempt to disguise the method they are using so that their own values, or issues of policy do not appear to be an influencing factor. The judgement of Owen J in the High Court had the same outcome as the case ultimately did in the House of Lords, yet the judges gave very different reasons for reaching their decisions.
All the courts seriously contemplated the meaning of 'detained', and attributed various explanations to a word that at first appears perfectly straightforward. Owens use of a dictionary definition suggests that he is following the literal rule and following the statute methodically as a textual formalist. The approach adopted in the House of Lords was more realist in nature, with the golden rule applied to limit the problems that the decision of the Court of Appeal would have created.
The Court of Appeal did not take account of any policy issues in its decision, which followed the statute without taking into account common law which "permitted the detention of those who were a danger, or potential danger, to themselves or others, in so far as this was shown to be necessary" (Lord Goff of Chievely at p. 490). The House of Lords took the opposite approach, applying the principle of necessity thereby invoking common law. Despite the assertion that L was not by any means unlawfully detained because "the deprivation of liberty must be actual, rather than potential" (Lord Goff of Chievely at p.
485), the House of Lords still used the common law as their authority. This enabled the House of Lords to reverse the decision of the Court of Appeal, quite apparently on policy grounds. Lord Nolan and Lord Steyn both openly expressed their agreement with the Court of Appeals decision. That they allowed the appeal in the House of Lords clearly occurred on the policy grounds stated by Lord Goff of Chievely, regarding the number of patients that would require compulsorily detention if the Court of Appeals ruling remained unchallenged.
If the courts can use policy so blatantly to guide their decisions as they have in this case, further contemplation leads to the suspicion that it may affect more cases than the judicial system would like the general public to be aware of. As the courts are not a political or elected body it is not easily justifiable that they are able to make decisions based on policy.
Cases Pepper (Inspector of Taxes) v. Hart  A. C. 593 Regina v. Bournewood Community and Mental Health N. H. S. Trust, ex Parte L.  1 A. C. 458