In civil injury litigation, and products liability in particular, expert testimony regarding the mechanism of injury can be critical to the prosecution or defense of a claim. There has been some debate among practitioners and the courts regarding whether a biomechanical expert must also be a medical doctor in order to offer opinions regarding injury causation.

In Council v. State, 98 So. 3d 115 (Fla. 1st DCA 2012), Florida’s First District Court of Appeal weighed in on this issue. The court held that a non-medical, biomechanical expert may offer opinion testimony regarding the causation of an injury. In the underlying aggravated child abuse case in which the defendant allegedly shook a child and caused a brain injury, the defense sought to introduce testimony from a PhD biomechanics expert. The defendant’s expert proffered two opinions regarding the injuries: (1) the child could have sustained similar brain injuries by falling out of a bed; and (2) shaking alone could not have caused such injuries. The trial court excluded the expert testimony on the basis that the expert’s opinions might confuse the jury because they could not translate into a medical diagnosis regarding the extent of the injury.

The appellate court recognized Florida law bars non-M.D. biomechanics experts from offering opinions regarding the extent of an injury. However, the court explained that a biomechanics expert is properly qualified to offer an opinion as to the causation of an injury if the injury falls within the field of biomechanics. In this case, the expert was qualified to offer his opinions because the mechanisms of injury: a fall from bed or shaking, are within the field of biomechanics.

While Council involved a criminal case, the court’s holding is equally applicable to biomechanics experts in civil cases as well. Therefore, as long as the mechanism of the injury falls within the field of biomechanics, parties may use a biomechanics expert to offer opinions regarding injury causation. Counsel who choose to retain non-medical doctor biomechanic experts must be careful to ensure that the expert’s opinion does not stray into areas where medical expertise is required.