The Appellate Committee of the House of Lords has once again sought to clarify the burden of proof in civil proceedings:  In Re B (Children) (Fc) [2008] EWCA Civ 282.  It also decided that if a legal rule required a fact to be proved (”a fact in issue”), a judge … must decide whether or not it happened.  “There is no room for a finding that it might have happened.  The law operates a binary system in which the only values are 0 and 1.  The fact either happened or it did not.  If the tribunal is left in doubt, the doubt is resolved by a rule that one party or the other carries the burden of proof.  If the party who bears the burden of proof fails to discharge it, a value of 0 is returned and the fact is treated as not having happened.  If he does discharge it, a value of 1 is returned and the fact is treated as having happened.”  (per Lord Hoffmann)  Lady Hale added that if the judiciary in this country regularly found themselves in the state of mind where it could not [applying the appropriate burden and standard of proof] reach a conclusion, our civil and family justice systems would rapidly grind to a halt.  A judge was not permitted to sit on the fence.  He had to find for one side or the other.  Sometimes the burden of proof would come to his rescue:  the party with the burden of showing that something took place would not have satisfied him that it did.  But generally speaking a judge was able to make up his mind where the truth lay without needing to rely upon the burden of proof.

The standard of proof in civil cases, that is to say, the degree of persuasion which the tribunal must feel before it decides that the fact in issue did happen is that the occurrence of the fact in question was more likely than not. 

Some confusion had been caused by dicta which suggested that the standard of proof may vary with the gravity of the misconduct alleged or even the seriousness of the consequences for the person concerned.  Lord Hoffmann thought the time had come, once and for all, to say that there was only one civil standard of proof and that was proof that the fact in issue more probably occurred than not.

On the notion of inherent probabilities which Lord Nicholls had referred to in In re H (Minors) (Sexual Abuse: Standard of Proof) [1996] AC 563, Lord Hoffmann emphasised that Lord Nicholls was not laying down any rule of law.  The learned Lord had said, “the court will have in mind as a factor, to whatever extent is appropriate in the particular case, that the more serious the allegation the less likely it is that the event occurred and, hence, the stronger should be the evidence before the court concludes that the allegation is established on the balance of probability.  Fraud is less likely than negligence.  Deliberate physical injury is usually less likely than accidental physical injury.  A stepfather is usually less likely to have repeatedly raped and had non-consensual oral sex with his under age stepdaughter than on some occasion to have lost his temper and slapped her.  Built into the preponderance of probability standard is a generous degree of flexibility in respect of the seriousness of the allegation.”  There is, however, only one rule of law:  namely, that the occurrence of the fact in issue must be proved to have been more probable than not.  Common sense, not law, requires that in deciding this question regard should be had to whatever extent appropriate, to inherent possibilities.  Therefore, if a child alleged sexual abuse by a parent, it was common sense to start with the assumption that most parents do not abuse their children.  But that assumption may swiftly be dispelled by other compelling evidence of the relationship between parent and child or parent and other children.

Lady Hale drew attention to Lord Lloyd’s opinion in In re H:  “In my view, the standard of proof ought to be the simple balance of probability however serious the allegations involved …”  He did not find it useful to use expressions such as the cogency of the evidence needed to tip the balance because, firstly, they were no more than statements of the obvious and, secondly, there was a danger that repeated use of the words would harden into a formula which, like other formulas (especially those based on metaphor) may lead to misunderstanding.

Lady Hale added that Lord Lloyd’s prediction proved only too corect.  Lord Nicholls’ nuanced explanation left room for the nostrum “the more serious the allegation, the more cogent the evience needed to prove it” to take hold and be repeated time and time again in fact finding hearings …”  It was time for us to loosen its grip and give it its quietus.