Legal Update: The dangers of ‘pseudo maths’ in civil litigation

We are taught from a young age, 1 + 1 = 2 and that is a fact.

That may be so, but in Law, and other professions, mathematics cannot be relied upon when making binary decisions. The court has recently rejected the use of percentages as a means of establishing whether or not a young girl died by accident or homicide.

There is a lesson to be found for everyone in this harrowing case…

 

The Case Study: A (Children) [2018] EWCA Civ 1718

In the precedent setting case of A (Children) 2018 in the Court of Appeal, a 10 year old girl was found dead in her bedroom. Initially it was thought to be a tragic accident. It was later discovered she had other injuries, probably inflicted about 12 hours before she died. In the view of the experts, the other injuries found on the girl’s body made it more likely that the neck injuries were deliberately caused, probably in some sexually motivated homicide.

In family and civil cases, a claimant has the burden of proving that a defendant acted incorrectly on the “balance of probabilities”. The balance of probabilities’ is the standard of proof used in all civil and family court proceedings and is used to determine whether something did or didn’t happen. Although this case was determined in the context of family cases, the judge expressed that it is likely to be applicable to civil cases in a similar way.

The Claimant must provide the court with sufficient evidence to show that there is more than a 50% chance that the Defendant has, for example, acted negligently or, in this case, whether or not death was accidental.

The court has held that this simple mathematical approach to determining evidence is not good enough. “The inherent probabilities are simply something to be taken into account, where relevant, in deciding where the truth lies”[1] but not to be used alone.

In this tragic case, it was determined that there was a 45% chance that the young girl’s death was by a perpetrated act…just below the threshold of 50%.

The Court of Appeal disagreed with this mathematical approach and held that the burden of proof in civil cases is often described as requiring a probability of more than 50%; but even then, this approach can carry a danger of “pseudo-mathematics” (or inaccurate calculations).

It was determined that assigning separate percentages to several possibilities of a case was “over-formulaic and intrinsically unsound”.

 

What can be learnt from this?

We all use the balance of probabilities to make personal and commercial decisions, but much like the judgment on this case, taking a holistic approach is key. Figures can only support our argument but should not be used alone when making a binary decision.

The harrowing investigation into the young girl’s death is still ongoing and has been remitted for a re-trial…

[1] Mr A Hayden QC appeared on behalf of the Appellant Mother, quotes Baroness Hale speech found in judgement paragraph 10. http://www.familylawweek.co.uk/site.aspx?i=ed41507

This article is for educational purposes and is not legal advice. If you want to seek legal advice, please contact us on justice@griffin.law or call 01753 525923

By |2019-04-09T11:11:44+00:00August 24th, 2018|Changes in the law, Family Law, Litigation|0 Comments

About the Author:

Keeley Gregory
Keeley is a solicitor in Griffin Law's dispute resolution team. Keeley is particularly skilled at dealing with detailed matters having dealt with matrimonial, defamation and commercial matters..