A court may order separate trials of issues, claims or parties for convenience, to avoid prejudice, or to expedite and economise.
Common bifurcations. Liability and damages; a statute of limitations or contract-interpretation issue that could resolve the case; punitive damages, including the financial condition evidence; and coverage from the underlying claim.
Advantages. A liability trial is shorter and less expensive than a combined one, damages expert work may be avoided entirely, and prejudicial evidence relevant only to one phase is kept out of the other.
Disadvantages. Witnesses testify twice; the same jury may be unavailable for the second phase; overlapping evidence must be separated, which is not always possible; and the plaintiff loses the sympathetic damages narrative during the liability phase — which is why plaintiffs usually oppose.
Jury right. Bifurcation must not deprive a party of the right to have common issues decided by the same jury, which constrains splitting issues that overlap.
Timing of the motion. Early, so that discovery and expert work can be sequenced accordingly. A bifurcation ordered after all the expert work has been done saves nothing.
Phased discovery as a lighter alternative, achieving much of the cost saving without splitting the trial.