Why are reverse onuses problematic for the law of evidence? How should the problems they raise be resolved?
The legal burden of proof is the ‘legal obligation on a party to satisfy the fact finder, to a specified standard of proof, that certain facts are true’[1]. The evidential burden is the responsibility on a party to adduce sufficient evidence for the court to consider its case. As a general rule, the burden of proof lies on the prosecution in a criminal case. However, there are occasions when the burden, or onus, is reversed and a defendant finds themselves proving their own innocence. This can arise in three specific contexts in criminal law, express statutory provision, for example the Homicide Act 1957, s.2(2), provides it is for the accused to prove diminished responsibility if he chooses to rely on that defence. Implied statutory provision, for example Magistrates Court Act s. 101 states that if a person has as any part of his defence ‘any exception, proviso, excuse or qualification’ it is for him to prove. Finally, under the M’Naughten Rules[2] it is for the defendant to prove insanity if that is his defence. It should be noted, that wherever an accused carries the burden, the standard of proof is on the balance of probabilities and not beyond all reasonable doubt.
In civil cases the burden is on the complainant, again, the burden is reversed either expressly or impliedly by statute, for example s.171(7) of the Consumer Credit Act 1974 provides that where a person asserts a credit agreement is extortionate within the terms of the Act it is for him to prove. However, in a civil case the parties can come to an agreement regarding who should carry the burden. Where the terms of this are ambiguous it becomes a matter for the court to decide having regard to all of the terms of the agreement. The standard of proof is on the balance of probabilities in all civil matters regardless of who carries the burden. It is understandable that an accused should have a lesser standard of proof in a criminal case as often a persons liberty is at stake, however, expecting a person to prove a fact in issue to the same standard as the person who has made the complaint is, on the face of it, unfair. For the purposes of this piece the focus shall be mainly on criminal cases, as that is where the most controversy arises.
The conspicuous problems with reverse onuses are that they, on the surface, conflict with everything that we know about the law, most importantly, that the accused is, innocent until proven guilty, consider Viscount Sankey LC’s much quoted dictum in Woolmington v DPP[3],
‘Throughout the web of the English criminal law one golden thread is always to be seen, that it is the duty of the prosecution to prove the prisoner’s guilt subject to …the defence of insanity and subject also to any statutory exception’[4].
As stated, in civil cases it is well known that ‘he who asserts must prove’. The presumption of innocence is a cornerstone of the criminal justice system and is safeguarded in Article 6(2) of the European Convention of Human Rights (the Convention), to require the defendant to discharge that burden seems directly opposed to that right. In terms of civil cases, Lord Maughan in Josephine Constantine Steamship Line Ltd v Imperial Smelting Corp Ltd[5] summed the position up most accurately when he said that this principle is ‘founded on considerations of good sense which should not be departed from without good reason‘. A further difficulty is that, by necessity, whoever has the legal burden of proof also carries the evidential burden of proof as one cannot be discharged without the other.
There have been numerous comments on the effect of reverse onuses and their effects. One suggestion is that reverse onuses should only ever require the accused to adduce evidence to support their defence[6], and the prosecution should retain the burden of proving the elements, or gravamen, of the offence[7]. Another argument, used when discussing automatism, is that by shifting the burden a defence becomes more problematic and therefore less easy for the defence to rely upon[8]. This is problematic in terms of fairness, if a defence is available to an accused, should they not be able to rely on it, where appropriate, without altering the standard that they are to meet? One writer speaking of the creation of the adverse inference[9] has gone so far as to suggest that the accused should have the burden of showing a lack of intent, motivation or care to commit the offence charged[10], though to adopt that as a general rule would hopefully not withstand a challenge under Article 6(2).
The current position is that reverse onus clauses are not incompatible with Article 6(2) of the Convention where the accused has enjoyed a fair trial. In order to allow for some flexibility on this point it has been held that if imposing a legal burden on an accused prevents this the burden should be read down to be evidentiary only, if that is not possible then the exception should be declared incompatible with Article 6(2). If, it is found that the burden can be imposed on the accused it must be justified and proportionate as per R v Lambert[11]. This conclusion has been reached after the issue has been before the courts on numerous occasions. Consideration of these cases is the best way to demonstrate how problematic reverse onus clauses actually are. In R v Hunt[12] the House of Lords held that subject to exception the burden of proof would be on the prosecution, where ‘linguistic construction’ did not properly indicate who should have the burden the court should have regard to other considerations, not least, the idea that Parliament would not easily intend to place the burden on the defendant, the mischief the section was aimed at and other considerations such as the ease or difficulty the party would have in discharging the burden.
The notion that Parliament would not create exceptions to the burden of proof is an interesting one. As Dennis points out,
“At another, deeper level, the presumption of innocence reflects moral and political values which are regarded as sufficiently important in liberal states to elevate the rule about the burden of proof to the status of a fundamental human right.”[13]
This is undoubtedly correct; however, it does highlight the problems caused by reverse onus clauses. If the presumption of innocence is to be held in such esteem as to be a fundamental human right, the interference should surely be kept to a bear minimum. Equally, like all human rights, it is subject to the ‘catch all’ caveat of public interest and as such is not inviolable. In Lambert the presumption was considered so important that the burden borne by the accused should be merely evidential where an offence carried a lengthy sentence or the culpability was identifiable. The note worthy point about this is that the exception in Lambert was statutory[14] and the consensus was supposed to be, according to R v Hunt that no exception would be made without good reason.
In Attorney General’s Reference No 1 of 2004[15] the Court of Appeal attempted to deal with reverse onuses emphatically, laying down no less than ten points for guidance, there is insufficient space here to discuss these in any real detail, suffice it to say that R v Johnstone[16] , a case relating to s. 92(5) Trade Marks Act 1994, should be considered the latest word. This House of Lords in this authority balanced the public interests against the interests of the individual as regards to reverse onuses. The Appeal Court also pointed out that both English common law and Article 6(2) both permit reverse onuses and a reverse onus is likely to be justified if the overall burden remains with the prosecution. Further, the exception should go no further than reasonably is necessary but it should be borne in mind that Parliament would not have created the exception without good reason (R v Hunt) and a merely evidential burden will not infringe Article 6(2). The guidelines also stated that where an exception is justified the court must construe the ‘realistic effects’ of the burden and accordingly the easier a burden is to discharge the more likely it is to be justified. Again, approval of the common strand was given, that the most important issue is can the accused still enjoy a fair trial. Finally, the need for a reverse burden is not necessarily reflected in the gravity of the offence and where guidance from the European Court of Human Rights is needed it is to be found at paragraph twenty eight of Salabiaku v France[17],
“Article 6(2) 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 maintains the rights of the defence.”
While these guidelines appear to follow a common sense and none to controversial path, they have however, not been explicitly approved by the House of Lords in fact, in Sheldrake v DPP[18] the House reiterated that what is most important is that the accused has enjoyed a fair trial were a burden has been imposed on him/her.
In conclusion, reverse onuses are problematic for the law of evidence because, despite a wealth of case law, there is still no clear cut answer on when the onus should be reversed and whether or not shift should be in relation to the legal or evidentiary burden, or both. However, surely this is just semantics, how could an accused possibly discharge the burden of proof without adducing sufficient evidence to allow him/her to do so and vice versa, if you are adducing sufficient evidence to prove your own defence are you not then discharging the legal burden of proof? The confusion surrounding this issue impedes the proper growth and development of the law of evidence and this can only be resolved with a uniform, but flexible standard on reverse onuses. While too robust a test will not assist in the matter, good, clear guidance will. As we have seen, this has already been attempted by the Court of Appeal and seemingly only partially accepted and since Sheldrake was finally heard in the House of Lords the position is not much clearer. Perhaps the problems created by reverse onuses could be better solved if it were the case that an accused could only be given the evidential burden of proof having regard to the fact that we have seen that such a burden cannot be incompatible with Article 6(2) and sits more comfortably alongside the privilege against self incrimination.
Bibliography:
Books:
Blackstone’s Criminal Practice 2004, (Oxford)
Choo, A., Evidence, (Oxford: 2006)
Dennis, I.H., The Law of Evidence, [2nd Ed], (Sweet and Maxwell: 2002)
Hannibal, M. & Mountford., The Law of Criminal and Civil Evidence, Principles and Practice, (Longman: 2002)
(NB Hannibal & Mountford have subsequently issued five online updates to this book that can be found at http://www.booksites.net/download/hannibal/download.htm)
Munday, R., Evidence, [3rd Ed], (Oxford: 2005)
Simester & Sullivan, Criminal Law, (Hart Publishing: 2004)
Journal Articles:
Cooper, S., Human Rights and Legal Burdens of Proof, Web Journal of Current Legal Issues, [2003], (3)
Cooper, S., Provocation and the Evidential Burden, Web Journal of Current Legal Issues, (1997)
Glancy D.G. et al., A Comparison of R v Stone and R v Parks: Two Cases of Automatism, The Journal of the American Academy of Psychiatry and the Law, (2002), (30), pp 541 – 547
Glover, R., Sheldrake Regulatory Offences and Reverse Legal Burdens, Web Journal of Current Legal Issues, [2006], (4)
Ingram B.L, The right of silence, the presumption of innocence, the burden of proof, and a modest proposal: a reply to O’Reilly, Journal of Criminal Law and Criminology, Vol. 86, 1996
Jones, T.H., Insanity, Automatism and the Borden of Proof on the Accused, Law Quarterly Review, (1995) 111, p 475
Stein, A., After Hunt: The Burden of Proof, Risk of Non-persuasion and Judicial
Pragmatism Modern Law Review (1991) 54, 570.
World Wide Web:
Case Law:
Josephine Constantine Steamship Line Ltd v Imperial Smelting Corp Ltd [1942] AC 154
Attorney General’s Reference No 1 of 2004 [2004] EWCA Crim 1025
R v Hunt [1987] AC 352
R v Johnston [2003] UKHL 28
R v Lambert [2001] UKHL 36
Salabiaku v France (1988) 13 EHRR
Sheldrake v DPP [2004] UKHL 43
Woolmington v DPP [1935] AC 462
Footnotes
Updated 16 March 2026
This article was written in approximately 2005–2006 and reflects the law as it stood at that time. The core legal principles discussed remain broadly accurate, but readers should be aware of several important subsequent developments.
Diminished responsibility: The article cites s.2(2) of the Homicide Act 1957 as placing the legal burden on the accused to prove diminished responsibility. This remains the position, but the defence itself was substantially reformed by s.52 of the Coroners and Justice Act 2009, which replaced the original statutory wording with a revised definition. The burden of proof on the accused on the balance of probabilities is unchanged, but the substantive elements of the defence are different from those applicable when this article was written.
Consumer Credit Act 1974: The article references s.171(7) regarding extortionate credit agreements. The Consumer Credit Act 2006 replaced the ‘extortionate credit bargain’ provisions with an ‘unfair relationships’ test under ss.140A–140D of the 1974 Act (as amended). The burden provisions under the new regime differ; under s.140B(9), once a debtor alleges an unfair relationship, the burden shifts to the creditor to show the relationship is not unfair. Readers should consult the amended Act.
R v Johnstone: The article treats R v Johnstone [2003] UKHL 28 as the leading authority on reverse onuses under the Trade Marks Act 1994. However, Sheldrake v DPP [2004] UKHL 43 (also cited in the article) is generally now regarded as the primary House of Lords authority reconciling the competing approaches in Lambert and Johnstone. Sheldrake confirmed that whether a reverse burden is compatible with Article 6(2) depends on whether it is reasonable and proportionate in all the circumstances. The approach in Johnstone has been treated with some caution in subsequent case law, and Sheldrake is the more reliable starting point.
Article 6(2) and the Human Rights Act 1998: The article’s analysis of compatibility with Article 6(2) of the ECHR remains fundamentally accurate. Courts continue to apply the reasonable and proportionate test from Lambert and Sheldrake, reading down legal burdens to evidential burdens where necessary under s.3 of the Human Rights Act 1998, or making declarations of incompatibility under s.4. This approach has been confirmed in subsequent case law.
Magistrates’ Courts Act 1980, s.101: The article refers to this provision (spelling the Act name incorrectly as ‘Magistrates Court Act’). Section 101 remains in force and the principle it embodies is unchanged, though its precise scope continues to be shaped by case law.
General note: The article’s bibliography and case law references reflect sources available up to approximately 2006. Students should consult current editions of the textbooks cited and check for more recent case law and commentary, particularly on the interaction between reverse burdens and Article 6(2) following Sheldrake.