Mock jurors made mistakes assigning liability even though the civil standard of proof and the evidence were clear and precise : mock jurors set aside the standard of proof

Abstract

The standard of proof in Canadian civil litigation is: If it is “more likely than not”, or, at least 51% likely the defendant caused the plaintiff damage, the defendant is liable (Kaheiro & Stanton, 1985, p. 160; Redmayne, 2004, p. 171; F.H. v. McDougall, 2008). This study investigated the willingness of mock jurors to assign liability if the likelihood the defendant caused the damage was 5%, 50%, 51%, or 95%, and damages were $5,000, $1,000,000, or unspecified. The number of participants, who correctly assigned liability when the evidence against the defendant was sufficient, or did not when it was insufficient, was only 57.6% (n=204, N=354), but 95.6% (n=86, N=90) if they reported they used the standard. In contrast, significantly fewer participants, 44.7% (n=118, N=264),who preferred more, or different evidence, before assigning liability to a defendant, made the correct decision (z= 8.432, p< .0001, 95% C.I= 0.3908 - 0.6272).