A new court practice rule will affect the timing of motions to bar crucial expert testimony. A motion in limine is commonly brought shortly before trial to allow a trial judge to trim issues of evidence to be admitted and streamline the actual trial. But a motion to bar an expert from testifying can be distinctly different. If the adversary’s case will fail without the expert, the motion is tantamount to a dispositive motion for summary judgment and must be made well ahead of trial.

Under the new court rule such a motion must now be made within the time frame for summary judgment motions, usually at least 30 days before trial. And if counsel waits until the eve of trial to file the motion as a motion in limine, the court may refuse to hear it. The reason, according to a 2015 Appellate Division case that spawned the new rule, is that such a motion made just before trial denies the adversary due process of law.

In Cho v. Trinitas Regional Med. Center, an appellate court grappled with a motion brought one day before jury selection, to bar plaintiff’s medical-malpractice expert witness from testifying. The witness was needed to sustain plaintiff’s burden of proof. So, as the court stated, this motion was really one for summary judgment because it could end the case, which should have been brought well ahead of trial to permit the adversary time to respond. The trial court granted the motion as one in limine, and dismissed the complaint. The Appellate Division reversed. Disguising a motion for summary judgment as a motion in limine denied plaintiff a fair opportunity to respond to the complaint-killing motion. Thus, the trial court’s ruling denied plaintiff fundamental due process. The Appellate Division stressed that the timing and sequence of a motion for summary judgment gives a reasonable framework to ensure due process.

The new rule applies to plaintiffs and defendants, and refers broadly to all types of expert witnesses, such as doctors, engineers, architects, accountants, economists, contractors, insurance and accident-reconstruction experts, to name a few, and without regard to the nature of the case. If a successful motion to bar an expert, such as an engineer in a product liability case, would lead to summary judgment, then the motion must be as one for summary judgment.

The rule can also be a blessing for defendants. A successful motion to bar expert testimony can lead to summary judgment well before trial. Judges hearing motions to bar critical expert testimony may no longer refer them to the time of trial as motions in limine, a frequent practice. These motions must be addressed when made, just as are motions for summary judgment. This is a good development for defendants.

So when your attorney asks authority to make an early motion to bar plaintiff’s expert, that just may be very good advice.