Cady v. Ride-Away Handicap Equipment Corp., 702 F. App'x 120

Background

Cady, driver of a 2007 Buick Terraza fitted with an AEVIT drive-by-wire system for his quadriplegic son, was severely injured in a single-vehicle crash and sued EMC (designer) and Ride-Away (installer) for product liability, negligence, failure to warn, breach of warranties, fraud, and related claims.
The van had AEVIT servos that actuate OEM pedals via a roller contacting an L-shaped brake extension; system includes an owner’s manual and multiple warnings requiring trained operators and a Safety Detent Pin for OEM mode.
Cady had not been trained on AEVIT; his son (trained) had driven earlier and reported accelerator problems. Cady attempted but failed to engage the Safety Detent Pin, then drove in “mixed mode” (AEVIT hand controls for steering/brake, foot for gas) after a parking-lot test drive.
During the downhill approach before the crash, AEVIT data showed brakes called for but speed briefly increased; post-crash inspections showed the brake roller’s position ambiguous (some inspections showed overlap, another showed roller beneath pedal after vehicle movement).
The district court excluded Cady’s engineering expert (Mark Ezra) under Fed. R. Evid. 702/Daubert and granted summary judgment for defendants, finding affirmative defenses (contributory negligence, assumption of risk), product misuse, and failure to heed warnings barred recovery. The Fourth Circuit affirmed.

Issues

Issue	Plaintiff's Argument	Defendant's Argument	Held
Admissibility of expert causation testimony (Rule 702/Daubert)	Ezra’s inspection and AEVIT data support a reliable engineering opinion that the brake roller migrated and caused brake failure.	Ezra’s methodology was flawed: he failed to test residue, quantify loads, consider frame deformation, or rule out alternative causes; opinion unreliable.	Court: Exclusion proper — Ezra’s omissions and methodological gaps made his opinion unreliable.
Sufficiency of evidence on causation to avoid summary judgment	Ezra was the sole causation evidence; thus his testimony was sufficient and should be admitted.	Without admissible expert evidence, plaintiff has no proof of causation and summary judgment is proper.	Court: Because Ezra was excluded, plaintiff lacked causation evidence and summary judgment for defendants was proper.
Applicability of affirmative defenses (assumption of risk / contributory negligence)	Cady contested that assumption of risk/contributory negligence should not bar his claims.	Defendants argued Cady knowingly operated a malfunctioning, warned-against system without training and in mixed mode, assuming the inherent risk.	Court avoided detailed ruling on merits because summary judgment was warranted on evidentiary grounds; concurring judge would affirm on assumption of risk as alternate ground.
Treatment of competing experts (consistency/fairness)	Excluding Ezra while admitting defendants’ experts was arbitrary because experts used similar data.	District court permissibly assessed reliability and found Ezra’s method deficient; admission of other experts not challenged here.	Court: No abuse of discretion; differences in methodology justified differential treatment.

Key Cases Cited

Daubert v. Merrell Dow Pharm., 509 U.S. 579 (expert testimony admissibility framework)
Kumho Tire Co. v. Carmichael, 526 U.S. 137 (trial judge’s gatekeeping duty applies to all expert testimony)
Cooper v. Smith & Nephew, Inc., 259 F.3d 194 (Fourth Circuit standard for expert admissibility review)
Westberry v. Gislaved Gummi AB, 178 F.3d 257 (focus on expert methodology over conclusions)
Bryte ex rel. Bryte v. Am. Household, Inc., 429 F.3d 469 (affirming exclusion where methodology flawed)
Oglesby v. Gen. Motors Corp., 190 F.3d 244 (affirming exclusion of unreliable expert testimony)
Owens-Illinois, Inc. v. Armstrong, 326 Md. 107 (causation necessary element in strict liability actions)
Pittway Corp. v. Collins, 409 Md. 218 (negligence requires proximate causation)