MEDICOLEGAL COLUMN: The Importance of Expert Testimony at Trial

By: Glenn W. Dopf, JD, LLM; Martin B. Adams, JD | Posted on: 04 Jan 2023

A trial of a medical malpractice action is frequently called a “battle of the experts.” Plaintiffs call their experts to establish alleged departures from the standards of good and accepted medical practice and to establish proximate causation between the departures and the claimed injuries. Defendants adduce expert medical testimony to defend the medical care, show the jury that Defendants at all times conformed to good and accepted standards of medical practice, and prove that Defendants did not proximately cause any injuries.

Necessity of Expert Medical Testimony

In order to successfully prosecute a medical malpractice action, a Plaintiff must produce at trial expert medical testimony, unless the alleged malpractice could be understood by a lay jury without the need for expert testimony and that would be an unusual situation. The reason is that the medical issues that Plaintiff must prove generally cannot be evaluated by lay jurors, who lack medical knowledge and lack experience in medical care.

“… as a general rule, a departure from [a] standard of care, whether it be at the diagnostic or treatment stage, must be established by expert testimony, except if the lack of care is so obvious as to be within the laymen’s common knowledge.”1

Proof of Urological Malpractice Requires Expert Proof

Courts recognize that a patient’s “urological condition, and the treatment he received or should have received for the same, [are] matters beyond the obvious common knowledge of the jury.”2

In Sousa v Chaset, Plaintiff did not offer any expert testimony showing how the Defendant urologist violated any duty of care. The state Supreme Court held that the trial court properly directed a verdict for Defendant on the negligence count. “… plaintiff provided no expert testimony to show how anything [defendant] had done departed from the standard of care that he should have provided… [D]iagnostic tests of a urethroscopy and a cystoscopy, the surgical procedure of a meatotomy, and the possible or probable side effects of specific medications plaintiff was taking are all matters beyond the ordinary knowledge of laypersons…,” held the state’s High Court.

Expert Testimony as to the Standard for Reviewing Medical Records

Expert medical testimony may be required to establish a standard of care and the skill required of a urological surgeon when reviewing a patient’s medical records prior to performance of surgery.

In a malpractice case against a surgeon, Plaintiff alleged that the surgeon was negligent in failing to consult the patient’s past medical record. Plaintiff argued that if his 15-year-old hospital record had been reviewed, then the surgeon would have discovered a problem encountered in the patient’s earlier surgery involving insertion of a catheter and would have been able to properly inform Plaintiff of the possible catheterization problem and the need to perform a cystostomy placement. Plaintiff contended that, if he had received that information, he would not have consented to the surgery. The surgeon’s motion to dismiss was granted because Plaintiff had no expert witness to establish Defendant’s negligence. “Whether or not physicians have a duty to review a 15-year-old medical record on a patient to ascertain potential complications is not a matter that is so obvious as to be within the comprehension of a layperson,” observed the Appellate Court. “A person untrained in medicine and surgery is certainly not equipped with the necessary information to determine the amount of investigation that is required by a physician prior to undertaking surgery.”3

Dismiss Plaintiff’s Lawsuit at the Close of Plaintiff’s Trial Presentation

A Plaintiff at trial who does not offer sufficient expert medical testimony on both departure and causation issues may find the Judge dismissing the case once Plaintiff’s counsel “rests” (advises the Judge that Plaintiff has completed his or her presentation of proof).

A plaintiff who “fail[s] to adduce expert testimony to establish the standards of care…; that the defendants departed from good and accepted practice…; or that the [treatment or failure to treat]… proximately caused her injuries… fail[s] to establish a prima facie case of medical malpractice…”4

The Defendant-surgeon’s Motion at the close of Plaintiff’s case in Pieter v Polin to dismiss the complaint was granted because Plaintiff failed to adduce expert testimony to establish the standards of care applicable to performance and interpretation of cardiac diagnostic tests and the development and execution of treatment plans, interpreting the results of catheterizations, making the determination to proceed with bypass surgery, or performing the surgery. Plaintiff also did not provide any expert medical testimony to show that the performance of a second catheterization or the failure to perform an intravascular ultrasound proximately caused her injuries.

Pretrial Dismissal if Expert Medical Testimony Is Insufficient

A Plaintiff who does not produce expert medical testimony faces the prospect of having his or her medical malpractice lawsuit dismissed.

Defendants frequently try to get lawsuits dismissed prior to trial, through a written application to the Judge (a “Motion”) for summary judgment. A Defendant will file an expert medical affidavit in support of his or her Motion. If Plaintiff does not respond with sufficient expert proof, then the Judge may grant Defendant’s Motion and dismiss the lawsuit before any trial.

A Defendant urologist was granted pretrial Motion for summary judgment in Ziobron v Squires, 907 NE2d 118 (Ct App Ind 2008) because Plaintiff failed to meet her burden of rebutting, with an expert opinion, a medical review panel’s finding that the Defendant health care provider met the applicable standard of care. Plaintiff had claimed that the Defendant urologist negligently performed a bladder sling procedure. The Appellate Court held that a urologist’s “method of preparing for [plaintiff’s] surgery, the lifespan of a bladder sling, and the likelihood that a urological patient will re-exhibit urethral hypermobility symptoms or develop a cystocele five years after a bladder sling surgery are not within the realm of a layperson’s knowledge and, thus, require expert testimony.”5

In summary, for a patient to prevail at trial, he or she generally must produce expert testimony as to both negligence and causation. Testimony on negligence without causation is insufficient and vice versa.

  1. Young v Park, 417 A.2d 889 (Sup RI 1980).
  2. Sousa v Chaset, 519 A2d 1132 (Sup RI 1987).
  3. Kennis v Mercy Hosp Med Ctr, 491 NW2d 161 (Sup Iowa 1992).
  4. Pieter v Polin, 148 AD3d 1193, 50 NYS3d 509 (2d Dep’t 2017).
  5. Ziobron v Squires, 907 NE2d 118 (Ct App Ind 2008).