Dateline: July, 2007, Issue 5

How do bifurcated versus unitary trials affect jurors' verdicts?

Horowitz and Bordens (1990) studied the effects of bifurcated versus unitary trials in a mass toxic tort case that was based on the facts of Wilhoite v. Olin Corp., CV 83-5021 (N.D. Ala. 1985).

In this research, over 760 jurors heard, in some form, a four-hour videotape that presented issues of causation, liability, compensatory damages and punitive damages. Some jurors participated in a unitary trial, hearing all the issues at one time before rendering a verdict. Other jurors participated in a bifurcated trial, rendering verdicts after causation, liability and/or compensatory damages, before proceeding to punitive damages.

Most of the unitary trial juries decided in favor of the plaintiffs on liability, while a majority of the bifurcated trial juries decided in favor of the defendant. Bifurcated juries that found for the plaintiffs awarded higher overall damages.

In sum, unitary trials increase the likelihood a defendant is held liable, although with smaller (total) damage awards than bifurcated trials. Bifurcation reduces the likelihood a jury will find a defendant liable, but at the cost of higher overall damages should liability be found.

Source Horowitz, I.A. & Bordens, (1990). An experimental investigation of procedural issues in complex tort trials. Law and Human Behavior, 14, pp. 269-285.