The Use of Statistics in Courtroom: An Empirical Experience from Hong Kong

Abstract

When assessing future pecuniary loss in personal injury litigation, courts often use the multiplicand/multiplier approach. The objective is to calculate a lump sum amount to compensate the plaintiff for a stream of future lost earnings and/or a stream of future expenses.

Conventionally, the Hong Kong Courts followed the English authorities in choosing multipliers. Most judges select the multipliers by reference to a spread of multipliers in comparable English and Hong Kong cases. This conventional approach was first challenged in the Hong Kong Court of First Instance in 1995 (Chan Pui Ki (An Infant) v Leung On [1995] 3 HKC 732). The trial judge abandoned the conventional method of choosing multipliers and admitted actuarial evidence to calculate the appropriate multiplier. However, this decision was subsequently reversed by the Hong Kong Court of Appeal in 1996 which held that the conventional multipliers for the calculation of loss of future earnings should be maintained. The Court of Appeal also discouraged any further use of expert evidence given by economists and actuaries in Hong Kong personal injury litigation.

On the contrary, the House of Lords in England made a landmark decision (Wells v Wells [1999] AC 345). It approved actuarial evidence as the primary method of assessing future pecuniary loss.

In this respect, the socio-legal implications of the English House of Lords decision in Hong Kong will be analysed. In addition, the legal and actuarial principles in calculating multipliers will also be explored and examined.