In order to win a medical malpractice lawsuit, a patient must typically prove three basic elements 1) the existence of a doctor-patient relationship, 2) the doctor's negligence in providing treatment, 3) that the patient was in fact harmed by that negligence. The core of almost every medical malpractice case is the second element: establishing exactly how the doctor's conduct (including failure to act) rose to the level of negligence.
To prove negligence, it is usually necessary to retain an expert medical witness who has experience with the kind of procedure or health condition in question, and who has ties to the local medical community.
When trying to establish a health care provider's negligence, the medical expert's job is to convince the jury of two things:
In the sections below, we'll explain how an expert medical witness will prove the two prongs of the negligence element.
The "medical standard of care" is the yardstick by which a medical malpractice defendant's conduct is measured. Simply put, a doctor has a legal duty to provide a patient with the type and level of care that a prudent, similarly-trained and competent health care professional would provide.
An expert medical witness's first job is to show what the "standard of care" would be under the circumstances that led to the alleged malpractice. What would a prudent health care professional -- with similar education and training as the defendant, and in the same medical community as the defendant -- have done under the circumstances? What medical issues would have been considered, identified, and addressed? What course of treatment would have been chosen for the patient? How would a prudent and similarly-trained doctor have performed the procedure in question?
Usually, the plaintiff's medical expert is a local health care professional who specializes in the same medical area of expertise as the defendant, or has extensive experience with the health problem or medical procedure that is the subject of the medical malpractice lawsuit.
Your state might have laws that dictate who can serve as a medical expert in a malpractice case, or that spell out what kind of expert must testify to the merits of a medical malpractice lawsuit at the outset of the case (in some states, the initial civil complaint in a medical malpractice case must be accompanied by an affidavit signed by a medical expert).
For example, in Maryland, a medical expert witness is an individual who is a licensed professional -- or comparably licensed or certified professional under the laws of another jurisdiction -- who is knowledgeable in the accepted standard of care in the same discipline as the licensed professional against whom the claim is filed.
Next, the plaintiff's expert medical witness will offer an opinion on the defendant's actions (or failure to act) in light of the medical standard of care. This can range from a failure to properly diagnose a certain condition, to physical mistakes during surgery or some other medical procedure, and everything in between.
Every aspect of the case, including the plaintiff's medical records, will be scrutinized by expert witnesses retained by both sides of the case. Each side will present a detailed and thorough argument for precisely how the defendant doctor's provision of medical care deviated from the medical standard of care (this is what the plaintiff's expert will try to establish) or was in line with that standard (so the defendant's expert will say).
Right or wrong, when a close case involves complex medical testimony by a each side's expert witnesses -- the so-called "battle of the experts" -- the jury's decision may be based (at least in part) on how memorable an expert witness's testimony was, or how effective they were in making complex medical information understandable to a jury of laypersons.