burden of proof

It is a fundamental principle of English law that a litigant bears the burden (or “onus”) of proof in respect of the propositions it asserts to prove its claim. The burden of proof does not lie with the person who denies the allegation, however the party denying the allegation is able to admit evidence to show that what is alleged was not the case.

Unless the party is able to prove the fact by relying on judicial notice or a presumption, the fact must be proved by formal evidence.

Accordingly, the burden of proof is applied which requires a person to prove the facts that he relies upon. Once proven, the burden of proof shifts to the opposing party to disprove the fact in issue.

A claimant who fails to prove the facts which constitute the cause of action (such as a breach of contract) it will fail in its claim against the defendant. Likewise, a defendant that does not discharge the burden of proof in respect to its defence (and assuming the claimant proves its own case on the facts), the defence will not be successful.

The foregoing reflects the default position, however note:

1. The burden of proof may be reversed by statute or by common law.
2. The legal persuasive or probative burden of proof should be distinguished from the evidential burden of proof.
   The so-called evidential burden of proof is not a burden of proof at all. It is the requirement on the party bearing the burden of proof to adduce evidence to prove the fact alleged.
   In criminal proceedings, sufficient evidence must be produced in respect to an issue before the evidence may be put to the jury.
   For instance, before a defence of self-defence may be raised before the jury, the accused must produce some evidence that the defence is justifiable. This evidential rule excluded defences not supported by evidence from unnecessarily drawing the attention of the jury.

Civil Burden of Proof

In civil cases, whether or not the burden of proof has been discharged is decided by reference to the standard of proof in civil litigation, which is the balance of probabilities.  For example, in a negligence claim, the burden is on the claimant to prove that:

1. the defendant owed the claimant a duty of care;
2. there was a breach of that duty of care;
3. which caused damage.

Each of these elements of the tort of negligence must be proved on the balance of probabilities. If the claimant fails to do so, then she will not succeed in her claim.  The defendant will have an opportunity to contest the facts asserted by the claimant; this is what is referred to as the “shift of the burden of proof”, such that the defendant is able to adduce evidence to disprove the facts asserted by the claimant.

Therefore, if the defendant alleges that in fact it was the claimant's own negligence which had contributed to the harm, the burden will shift onto the defendant to prove that the claimant was contributory negligence. In fact, the burden of proof does not shift at all – it is an expression used to describe a practical method of assessing evidence adduced by both parties. Accordingly, at the trial, each party will bear the burden of proof. 

In summary, in order to be successful in civil proceedings, the claimant must prove by evidence (the evidential burden) the facts to the standard of the legal burden of proof, which is on the balance of probabilities.

Criminal Proceedings - Burden

In criminal proceedings, the prosecution bears the burden of proof in respect to charges to the criminal standard of “beyond a reasonable doubt”, as opposed to the balance of probabilities. The existence of the burden of proof on the prosecution to this standard encapsulates the presumption of innocence which lies in favour of the accused. The prosecution must:

1. satisfy the evidential burden. The evidential burden is the requirement to produce sufficient evidence to prove an issue at trial, or to show the existence or non-existence of a fact in issue. Where there is a failure to satisfy the evidential burden, that issue cannot be raised in Court;  and
2. prove the guilt of the defendant beyond reasonable doubt.

If however the defendant raises a defence such as self-defence, then he will have to bear the evidential burden of that issue.

In the landmark case of Woolmington v DPP (1935), the defendant was charged with the murder of his wife. The trial Judge directed the jury that once the prosecution had proved that the defendant had killed the deceased, it was then for the defendant to show that the killing did not amount to murder, that is, the defendant had to show that he did not intend to kill or cause grievous bodily harm. The defendant unsuccessfully appealed to the Court of Appeal but successfully to the House of Lords. Viscount Sankey LC held that the direction was improper and said:

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 what I have already said as to the defence of insanity and subject to any statutory exception.

Statutory Exceptions

Strict adherence to the presumption of innocence can pose difficulties for the prosecution and for public policy reasons. Therefore, there are numerous statutory exceptions to the Woolmington principle which shifts the burden of proof on the defendant in certain regulatory offences and for the protection of public interest.

Presumption of innocence

The presumption of innocence is fundamental to a fair trial. This is a principle of the common law and is stated in the Article 6(2) of the European Convention on Human Rights. 

Presumptions are basically a method of distributing the burden of proof on a particular issue, which could lead to the requirement of less evidence than would otherwise be necessary, or no evidence at all. Some presumptions are irrebuttable in that the Court is bound to draw a certain conclusion, whether or not there is evidence to the contrary, and in such circumstances, evidence in rebuttal will be inadmissible.

Defence of Insanity

Where the defendant pleads insanity, he bears the persuasive burden which is discharged on a balance of probability. However, if the prosecution raises the defence, they must prove it beyond reasonable doubt.

If, however, the defendant’s defence involves the pleading of issues such as non-insane automatism, provocation, self-defence, duress, and belief in lawful authority and mechanical defect, he bears the evidential burden and the onus of disproving them rests on the prosecution. In order to be successful in criminal proceedings, the prosecution must prove by evidence (the evidential burden) the facts to the legal burden of proof, which is ‘beyond a reasonable doubt’.

Strict liability and the Burden of Proof

There are certain cases which the law imposes strict liability on the defending party if the claimant (or prosecution) is able to prove a particular set of facts. Strict liability removes the burden of proving liability, and is applicable to both criminal and civil proceedings.