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The Crucial Role of Medical Expert Witnesses in Medical Malpractice Lawsuits

Understanding the Impact of Medical Expert Witnesses on Trial Outcomes

According to an article by Philip G. Peters titled “Twenty Years of Evidence on the Outcomes of Malpractice Claims” (2009)1, doctors lose 10% -20% of jury trials even when the evidence of negligence is weak, yet win 70% of cases with borderline evidence, and even win 50% of cases where the evidence strongly suggests negligence. These statistics suggest that even in the face of solid evidence in their favor, winning is far from a guarantee. The defense must be prepared to make a compelling case that the standard of care was met. On the other side of the courtroom, the plaintiff must prove to a jury that “more likely than not,” medical malpractice was committed, and convincing evidence alone may not be enough to win. With the burden of proof resting with the plaintiff, they must teach the jury about the four elements of medical malpractice: breach of duty, negligence, causation, and damages, and they must do so in language that the jurors can fully understand.

The Role of Medical Expert Witnesses in Simplifying Complex Medical Information

In a medical malpractice trial, medical expert witnesses are typically hired to a) review the medical records and provide an opinion as to whether the standard of care was met or breached and b) break down complicated medical information in a way that jurors can understand and guide them into making an informed decision. If the jurors are confused by medical jargon, they won’t be able to make an educated decision.

The Importance of Witness Credibility in Malpractice Cases

In the article “Heuristic processing can bias systematic processing: Effects of source credibility, argument ambiguity, and task importance on attitude judgment”2, the authors state that when a task is important and the evidence is ambiguous, the jurors will make their decision solely on the credibility of the witness.

Selecting the Ideal Medical Expert Witness

Because of this, selecting an ideal medical expert witness, one who is most likely to help you in your case goes well beyond just having a long and impressive-looking Curriculum vitae. In addition to being well-trained and with decades of experience, qualities such as likability and being relatable to a jury are also very important. Being a persuasive speaker who can break down complex medical terminology into language that a juror can easily understand is also of high value. All of these factors play a crucial role in clarifying medical facts and often determining the trial's outcome.

The Influence of Medical Expert Witnesses on Case Outcomes

Recent studies, including a review published in the Journal of the American Medical Association (JAMA)3, highlight the importance of medical expert witnesses. Their role is key in interpreting what really happened, arriving at the truth, and determining whether the standard of care was met.

Medical Expert Witnesses as Interpreters of Medical Evidence

Medical expert witnesses are the jury’s bridge between complex medical facts and the truth: what really happened? The expertise of a medical expert witness allows them to interpret medical evidence, often thousands of pages worth, in order to determine if the defendant’s actions were justified and consistent with best practices, and reinforce the legal arguments with solid medical evidence. This role is essential in crafting a persuasive argument.

The Value of Expert Testimony for Both Parties

Medical expert witnesses are valuable to both parties as they evaluate the evidence to best advise counsel as to whether their case has merit and whether or not the standard of care was met. Both the plaintiff’s attorney and the defendant’s attorney will often pay close attention to the opinions of the experts they have retained and use those opinions to guide them on decisions about moving forward.

Enhancing Credibility with a Respected Medical Expert Witness

Both the defense and the plaintiff’s credibility can be significantly enhanced by a well-respected medical expert witness. An experienced expert with a strong reputation adds significant weight to the respective party’s arguments. Their objective and professional testimony can influence the jury’s opinion, portraying the respective party’s case as based on sound medical science. This credibility is especially important during cross-examination, where the expert’s ability to remain calm and clear strengthens their respective party’s position.

The Essential Role of Medical Expert Witnesses

In medical malpractice lawsuits, medical expert witnesses are vital to both parties. They clarify complex medical issues and provide expert opinions as to whether standards of care were or were not met. Furthermore, medical expert witnesses provide highly valuable information and advice to their clients, both plaintiff attorneys and defense attorneys, which can significantly influence the path forward and potentially the outcome of a trial. As shown by recent research in the Journal of the American Medical Association3 and the New England Journal of Medicine4, using medical expert witnesses is a vital part of winning a malpractice lawsuit.


Do you have a question about a possible medical malpractice case? Call Dr. Lieberman today for a Free Consultation: 720-446-6828


1 Studdert, D. M., Mello, M. M., & Brennan, T. A. (2004). Medical Malpractice. New England Journal of Medicine, 350(3), 283-292.

2Chaiken, S., & Maheswaran, D. (1994). Heuristic processing can bias systematic processing: Effects of source credibility, argument ambiguity, and task importance on attitude judgment. Journal of Personality and Social Psychology, 66(3), 460–473.

3Ronquillo Y, Robinson KJ, Kopitnik NL, et al. Expert Witness. [Updated 2024 Feb 12]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from:

4 Brennan, T. A., Sox, C. M., & Burstin, H. R. (1996). Relation Between Negligent Adverse Events and the Outcomes of Medical-Malpractice Litigation. New England Journal of Medicine, 335(26), 1963-1967.


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