There are now many express and implied statutory examples where the burden of proof is reversed where the defendant must discharge a legal burden to avoid conviction. These provisions have aroused the interest of Europe as potentially violating the right to a fair trial as guaranteed by Art. 6 (2) of the European Convention on Human Rights and Fundamental Freedoms, now enshrined in our domestic law by the Human Rights Act 1998. The Courts have held, that where a legal burden is imposed, it must be legitimate and proportionate. Where it is not proportionate, the offending provision should be ‘read down’ so as to impose only an evidential burden on the defendant. As we shall explore, the law in this area is often complex and resembles a smorgasbord of often conflicting factors.


A central feature in most common law systems is that a defendant is presumed innocent and the prosecution have the burden of proving the guilt of the accused beyond reasonable doubt. The presumption of innocence is enshrined in the very fabric of English law and was evidenced in early cases such as R v Hobson where the Court held that ‘it is a maxim of English law that ten guilty men should escape rather than one innocent man should suffer.’ However, there are exceptions. Lord Sankey identified an exception to the golden thread in the form of statutory exceptions (Woolmington). This exception can be further subdivided into express and implied statutory provisions. There are a considerable number of legislative provisions that indicate expressly that the defendant must discharge the legal burden of proof in relation to some fact or issue at point within a case. A comprehensive study by Ashworth and Blake in 1996 concluded that forty per cent of indictable offences involved the defendant discharging a legal burden of proof for some element of the offence. One limitation of this study is that it only considered serious offences, triable on indictment and before the Crown Court. Munday insists that if summary offences before the Magistrates’ Court were also included the percentage would be much higher. Therefore, it is fair to conclude that the defendant will on many occasions be compelled to discharge the legal burden of proof. For example, the Homicide Act 1957, s.2 (2) which defines the defence of diminished responsibility, and states that ‘On a charge of murder, it shall be for the defence to prove that the person charged is by virtue of this section not liable to be convicted of murder’.  Furthermore, statutes may impliedly reverse the burden of proof. For summary offences, the relevant rule can be found in the Magistrates’ Courts Act 1980 s. 101 which provides that where a defendant relies on a defence involving an exemption, exclusion, proviso or excuse, the burden shall be on the defendant.


We therefore can confidently conclude that the ‘golden thread’ has never actually been absolute and continues to be weakened in the modern legal climate. The next issue we consider is whether the exceptions to the ‘golden rule’ represent a threat to human rights norms, namely the presumption of innocence and the right to a fair trial.


All reverse burdens must take into account the presumption of innocence enshrined in Art. 6(2) of the European Convention on Human Rights and Fundamental Freedoms. Art. 6(2) insists that ‘Everyone charged with a criminal offence shall be presumed innocent until proved guilty according to the law’. The inherent problem with reverse onuses is that they appear to fly in the face of this presumption of innocence and thus denies the defendant the right to a fair trial. This problem is exacerbated by the temptation for Parliament to employ reverse burdens as a weapon in the fight against serious crime (Munday 2007). The question that falls to be answered is whether it is ever permissible to impose a legal burden upon the defendant, or whether all such burdens are now outlawed as they impinge upon the fundamental principles of the presumption of innocence?


The issue was first heard in the higher courts in this jurisdiction in the case of R v Lambert where the appellant was convicted of possessing a controlled drug with intent to supply. This was in contravention of s. 5 of the Misuse of Drugs Act 1971. The appellant sought to rely on s. 28(3)(b)(i) which established a defence that the accused did not know or suspect that the bag he was carrying contained a proscribed drug. The trial judge concluded that to establish such a defence the defendant must ‘prove’ that he did not know or suspect the bag contained narcotics and insisted that the accused bore the legal burden of proof. This outcome was unsurprising given that the use of the verb ‘prove’ is the classic language of express statutory exceptions to the golden thread.


On appeal, the appellant argued that the trial judge erred in finding that the accused must discharge a legal burden and this was a clear violation of Art. 6(2). The appellant failed to persuade the Court of Appeal and the case proceeded to the House of Lords. The House of Lords dramatically overturned the decisions of both lower courts in a majority decision. The Court held that in light of the enactment of the Human Rights Act 1998, which weaved the Convention principles directly into the domestic law of this jurisdiction, the appellant should be charged with an evidential burden only i.e. adducing some evidence that he did not know or suspect the bag contained narcotics.


In order to achieve this result, the Court utilised s. 3 of the Human Rights Act 1998 to ‘read down’ the words ‘must prove’ in s. 28(3)(b)(i) as meaning ‘to adduce evidence of’. Once some evidence was proffered by the defendant, it was then the job of the prosecution to disprove this beyond reasonable doubt. The mechanism of reading down did injustice to the presumption that when a word is used in more than one place in a statute, a word will usually bear the same meaning: in this sub-section the verb ‘prove’ was used to identify the prosecution’s legal burden of proof. While this decision was radical in its straining of the meaning of s. 28(3)(b)(i), it should be noted that the Law Lords conceded that not every legal burden, whether express or implied, would necessarily violate Art. 6(2). The raises the difficult question of where we draw the line between acceptable legal burdens and those that violate Art. 6(2)?


In Lambert the Court emphasised that the prosecution always bear the primary obligation of proving the main elements of an offence. After that, the legality of the reverse burden would be assessed in light of all of the circumstances, including the aim of the legislation, the fact that Parliament had intended to pass such a statute, and the ease with which the prosecution could discharge the burden should it be placed on them. Every reverse burden will therefore involve a balancing exercise, involving several factors, to ensure that the burden is proportionate.


However, Lambert itself depicts the unpredictability of this proportionality exercise. If we analyse the judgments of all appellate judges that heard this case, we see that four judges found that s.28(3)(b)(i) was a disproportionate interference while four did not. If we factor in the decision of the trial judge, the majority of judges found no violation! Munday suggests that what lies at the heart of this divergence in opinion, is the ‘differing perceptions of the degree to which the state is entitled to deprive defendants of their customary protections in the interests of protecting society against the baneful effects of drug-dealing’. Judges therefore use human rights law as an instrument to override what have ‘traditionally been considered quintessentially political decisions’ (Munday 2007).


This divergence in opinion is plainly evident in Lambert. The majority emphasised that a conviction in the case could attract a sentence of life imprisonment. The majority cautioned against imposing a legal burden as it would allow an accused to be convicted where the jury might well believe he was innocent but had not persuaded them that he probably did not know the nature of what he possessed. However, Lord Hutton, in a powerful dissent, emphatically disagreed with the majority. Lord Hutton emphasised the ease with which the defendant could discharge an evidential burden, by adducing evidence in his statement or through evidence of a third party. This would then lead to the prosecution having to destroy the defence by leaving no reasonable doubt in the mind of the jurors that he knew he was in possession of a controlled drug. The judge urged that the threat of drugs to the wellbeing of the community justified a legal burden in this case.


After Lambert it was feared that Courts would ‘read down’ all legal burden as being evidential only, especially in situations involving serious crimes which attracted heavy punishments. However, in R v Johnstone the House of Lords sought to refine Lambert by adopting a more non-interventionist approach. Lord Nicholls opined that in reverse burden cases, the Courts enjoy a mere power of review, and should only differ from the intention of Parliament when it is clear that Parliament has failed to give sufficient important to the presumption of innocence. In Attorney General’s Reference (No 1 of 2004) the Court preferred the approach in Johnstone over Lambert and held that the former was the last word on the subject and the citation of other authorities should be discouraged. However, in the case of Sheldrake v DPP the Court held that Lambert should not be ignored and that it was perfectly compatible with Johnstone. Lord Bingham suggested that the differences in emphasis in the case ‘are explicable by the difference in subject matter of the two cases’.


However, the authorities have been criticised as not providing clear enough guidance on how to interpret statues that impose a reverse burden. The factors identified in Sheldrake above are indicative at best, but do not provide conclusive guidance (Tadros and Tierney 2004). It is therefore wholly understandable that the proportionality exercise has been described as an ‘imprecise science’ that involves balancing the egregiousness of the evil posed against society and the rights of the accused. Dennis concedes that it is difficult to discern any pattern within the case law on the relative importance of each factor, with the author indicating that ‘the justifiability of particular reverse onuses will resemble a forensic lottery’.