Justifications for reversing legal burden

11.103         The following section discusses some of the principles and criteria that may be applied to determine whether a criminal law that reverses the legal burden of proof may be justified.[161]


11.104         As discussed in Chapter 1, proportionality is, generally speaking, the accepted test for justifying most limitations on rights. The Human Rights Committee has noted that reverse burden offences are likely to be ‘compatible with the presumption of innocence where they are … reasonable, necessary and proportionate in pursuit of a legitimate objective’.[162] Some stakeholders expressly endorsed proportionality as a means of assessing justifications for reversals of the burden of proof.[163]

11.105         In other jurisdictions, it is accepted that a reversal of the burden of proof may be justified in some circumstances. The approach of the European Court of Human Rights to reverse onus provisions is set out in Salabiaku v France:

Presumptions of fact and law operate in every legal system. Clearly, the [European Convention]does not prohibit such presumptions in principle. It does, however, require the contracting states to remain within certain limits in this respect as regards criminal law.

… Article 6(2) [of the European Convention]does not therefore regard presumptions of fact or of law provided for in the criminal law with indifference. It requires States to confine them within reasonable limits which take into account the importance of what is at stake and maintain the rights of the defence.[164]

11.106         In the UK House of Lords, Lord Bingham summarised the proportionality test as it can be applied to the reversals of the burden of proof:

the substance and effect of any presumption adverse to a defendant must be examined, and must be reasonable. Relevant to any judgment on reasonableness or proportionality will be the opportunity given to the defendant to rebut the presumption, maintenance of the rights of the defence, flexibility in application of the presumption, retention by the court of a power to assess the evidence, the importance of what is at stake and the difficulty which a prosecutor may face in the absence of a presumption.[165]

11.107         Lord Bingham observed that such a test is context-specific, stating that ‘[t]he justifiability of any infringement of the presumption of innocence cannot be resolved by any rule of thumb, but on examination of all the facts and circumstances of the particular provision as applied in the particular case’.[166]

11.108         A number of considerations may be relevant to evaluating whether a reversal of the burden of proof is reasonable, necessary and proportionate in pursuit of a legitimate objective.

Where not an essential element of the offence

11.109         It is commonly acknowledged that shifting a legal onus onto the accused with respect to an element of an offence that is essential to culpability is an encroachment on the presumption of innocence, and more difficult to justify.[167] Shifting the burden of proof on such an issue involves the possibility of unfair conviction. In the Canadian Supreme Court, Dickson CJC said that

[i]f an accused is required to prove some fact on the balance of probabilities to avoid conviction, the provision violates the presumption of innocence because it permits a conviction in spite of a reasonable doubt in the mind of the trier of fact as to the guilt of the accused.[168]

11.110         Where a defendant bears the legal burden of proof on an issue essential to culpability, the result may be ‘seriously unfair, since a conviction might rest on conduct which was not in any way blameworthy’.[169]

11.111         By contrast, it may be more readily justifiable to shift the burden of proof on issues that are ‘optional exceptions to criminal responsibility’.[170]

11.112         Distinguishing between an issue that is central to culpability for an offence and optional exceptions to it can be difficult. Such distinctions are not always resolved by whether the issue is cast as a defining element of an offence or a defence to it. In the House of Lords, Lord Steyn noted that

[t]he distinction between constituent elements of the crime and defensive issues will sometimes be unprincipled and arbitrary. After all, it is sometimes simply a matter of which drafting technique is adopted: a true constituent element can be removed from the definition of the crime and cast as a defensive issue whereas any definition of an offence can be reformulated so as to include all possible defences within it. It is necessary to concentrate not on technicalities and niceties of language but rather on matters of substance.[171]

11.113         The Guide to Framing Commonwealth Offences recognises this difficulty. It states that placing the burden of proof on the defendant by creating a defence is more readily justified if the matter in question is not central to the question of culpability for the offence.[172]

11.114         Professor Jeremy Gans suggests that defences such as reasonable excuse or due diligence are examples of optional exceptions to an otherwise fully defined offence. In such cases, a shift in the burden of proof is ‘clearly justifiable’.[173]

11.115         In Lambert, the imposition of a legal burden on the accused to prove that he did not know that a package in his possession contained controlled drugs was considered to shift the burden on an essential element of the offence—it was an issue ‘directly bearing on the moral blameworthiness of the accused’.[174]

11.116         In that case, Lord Steyn observed:

in a prosecution for possession of controlled drugs with intent to supply, although the prosecution must establish that prohibited drugs were in the possession of the defendant, and that he or she knew that the package contained something, the accused must prove on a balance of probabilities that he did not know that the package contained controlled drugs. If the jury is in doubt on this issue, they must convict him. This may occur when an accused adduces sufficient evidence to raise a doubt about his guilt but the jury is not convinced on a balance of probabilities that his account is true. Indeed it obliges the court to convict if the version of the accused is as likely to be true as not.[175]

11.117         Professor Ian Dennis suggests that an exception to a principle that the defendant should not bear the burden of proof on an issue going to culpability—or ‘moral blameworthiness’—exists where the risk has been voluntarily assumed:

individuals who voluntarily participate in a regulated activity from which they intend to derive benefit accept the associated burden. This burden is the risk that they may have to account for any apparent wrongdoing in the course of that activity, even where the liability involves an adverse moral evaluation of their conduct. … An analogy might be made with the duties to account that are frequently placed on office-holders in various legal contexts, such as the conduct of corporate enterprises.[176]


11.118         The seriousness of a crime, it is sometimes suggested, justifies placing a legal burden of proof on the accused. However, this argument has also been criticised. Calling this the ‘ubiquity and ugliness argument’, Sachs J of the South African Constitutional Court in State v Coetzee said:

There is a paradox at the heart of all criminal procedure in that the more serious the crime and the greater the public interest in securing convictions of the guilty, the more important do constitutional protections of the accused become … The perniciousness of the offence is one of the givens, against which the presumption of innocence is pitted from the beginning, not a new element to be put into the scales as part of a justificatory balancing exercise. If this were not so, the ubiquity and ugliness argument could be used in relation to murder, rape, car-jacking, housebreaking, drug-smuggling, corruption … the list is unfortunately almost endless, and nothing would be left of the presumption of innocence, save, perhaps, for its relic status as a doughty defender of rights in the most trivial of cases.[177]

11.119         In the UK, the seriousness of the problem addressed by the offence has been routinely considered as one factor in assessing whether a reversal of the burden of proof is a proportionate response. In Lambert, the imposition of a legal burden of proof on the accused to prove that he did not know that a package in his possession contained controlled drugs was not considered a proportionate response to the ‘notorious social evil’ of drug trafficking.[178]

11.120         In Sheldrake v DPP, a legal burden on the accused to show that there was no likelihood of driving withan excess of alcohol was not considered disproportionate, given the legitimate objective of ‘prevention of death, injury and damage caused by unfit drivers’.[179] However, in the conjoined appeal of Attorney General’s Reference No 4 of 2002,despite the public interest in preventing terrorism, the House of Lords did not consider it justified to impose a legal burden on the accused to prove that an organisation was not a proscribed organisation on the date he became a member or began to profess being a member of that organisation, and that he had not taken part in the activities of the organisation at any time while it was proscribed.[180]

11.121         In R v Williams (Orette), the legal burden of proof on the defendant in a firearms offence to show that he did not know and had no reason to suspect that an imitation firearm was convertible to a useable firearm was considered justified, with one of the reasons for this being the seriousness of firearm offences and the need to protect the public.[181]

11.122         Alternatively, where the offence is one where the penalty is not severe, it may be more readily justifiable to shift the burden of proof on an issue. Examples might include ‘regulatory offences whose primary purpose is the efficient operation of matters within the public sphere, such as transport, traffic, manufacturing, environmental protection, control of domestic animals and consumer relations’.[182] Associate Professor David Hamer has argued that such regulations ‘play a crucial role in safeguarding the public interest. While the breach of regulations often carries the potential for extensive and severe harm, the penalties are often fairly minor’.[183]

Difficulties of proof

11.123         Reversing the onus of proof is sometimes said to be justified where it is particularly difficult for a prosecution to meet a legal burden.[184]

11.124         However, as the Guide to Framing Commonwealth Offences notes,

[t]he fact that it is difficult for the prosecution to prove a particular matter has not traditionally been considered in itself to be a sound justification for placing the burden of proof on a defendant. If an element of the offence is difficult for the prosecution to prove, imposing a burden of proof on the defendant in respect of that element may place the defendant in a position in which he or she would also find it difficult to produce the information needed to avoid conviction. This would generally be unjust.[185]

11.125         The Institute of Public Affairs submitted that difficulties associated with proof are not a sufficient justification for a reversal of the burden of proof, stating that ‘[t]he common law legal system is ideal not for the ease with which it allows for prosecutions, but for the protections it offers against an overbearing state’.[186]

11.126         Nonetheless, it may be considered justifiable to reverse the onus of proof on an issue that is ‘peculiarly within the knowledge’ of the accused. Such was the case in R v Turner, where the burden of proving that the defendant had the necessary qualification to kill game was considered to be peculiarly within the knowledge of the accused.[187] A number of submissions considered that a reversal of the burden of proof may be justified in circumstances where peculiar knowledge resides with the defendant.[188]

11.127         The Consumer Action Law Centre submitted that in corporate misconduct matters, the requisite knowledge and evidence ‘invariably exists within the corporate entity, so therefore it is appropriate that any burden of proof be reversed to that party’.[189] Jobwatch submitted that it may be appropriate to reverse the burden of proof ‘if it is particularly difficult to prove a case due to an imbalance of resources that favours the defendant’.[190]

11.128         Hamer has noted extraordinary proof imbalances are more likely to exist in the case of regulatory offences, and that reverse persuasive burdens ‘provide a practical way for the regulator to manage the cost of prosecutions’.[191]