Medical Expert Witness and Proving Malpractice

Medical malpractice law is based on concepts drawn from tort and contract law – commonly understood as liabilities arising from the delivery of medical care.  Malpractice suits are generally based on negligence, breach of contract (a treatment guaranteeing a certain result), intentional misconduct, divulgence of confidential information, defamation, insufficient informed consent, or the failure to prevent foreseeable injuries to third parties.  Out of these, the most common cause of medical malpractice suits is negligence.

Medical negligence, according to Black’s Law Dictionary, requires the plaintiff to establish the following:

  • the existence of the physician’s duty to the plaintiff, usually based on the existence of the physician-patient relationship;
  • the applicable standard of care and its violation;
  • the damages (a compensable injury);
  • the connection between the violation of the standard of care and the harm complained of.

Medical expert witness testimony is used by both the plaintiff and defendant in medical malpractice suits.  The expert witness testimony plays an important role in determining if malpractice occurred or not and by and large, the courts rely on this testimony to establish the standards of care germane to a malpractice suit.  In a nutshell, the expert witness testimony describes the standards of care relevant to the given occurrence, identifies any shortcomings to this standard and states whether the shortcomings are the most likely reason for the injury.  Without the medical expert witness testimony, juries who do not possess the same technical expertise would be at a loss to distinguish malpractice from mal-occurrence.  How exactly does an expert witness prove that malpractice has occurred?

Establishing the Standard of Care

According to the law of negligence, standard of care is “that degree of care which a reasonably prudent person should exercise in same or similar circumstances.”  In the case of medical malpractice this is understood to be, “that reasonable and ordinary care, skill, and diligence as physicians and surgeons in good standing in the same neighborhood, in the same general line of practice, ordinarily have and exercise in like cases,” and the defendant’s behavior  is compared with this standard.

The first job of an expert witness would be to establish the “standard of care” in relation to the medical occurrence.  This would be done by showing what a prudent health care professional, with similar education and training, would have done under the same circumstances.  What would be the medical issues considered and addressed, course of treatment chosen and followed and procedures performed by a similar healthcare professional?

Proving Breach of Standard of Care

Next, the plaintiff’s expert witness has to prove that there was a breach of the standard of care relevant to the medical occurrence.  Evaluation of factual testimony provided by other witnesses and going through medical reports and other test records are used to indicate if there has been any deviation from the acceptable standards.  Using these, the expert witness has to prove that the defendant’s care of the plaintiff was not up to the standard of care, as earlier determined.  If it is determined that the care provided was “substandard,” the expert witness may be asked whether the deviation could be the cause of the plaintiff’s injury.


The jury members are in the majority of cases, laymen in the field of medical science.  The outcome of the case depends on how well the expert witness has been able to make the jury members understand the complexities of the treatment and the whether there has been a deviation from the standards of care or not.




Medical Errors – The Third Leading Cause Of Death

Do you think that death certificates should along with stating the cause of death, also figure a column that states whether a preventable complication stemming from the deceased’s care contributed to the death – in simple words, if the death was caused due to a medical error?  In case you are wondering what brought about this question, here is a startling fact – according to a report published in BMJ, medical error is the third leading cause of death in the US.  The first two positions go to heart disease and cancer.

Martin Makary, MD, MPH, Professor of Surgery and Michael Daniel, research fellow, from Johns Hopkins University School of Medicine and authors of the report, believe that medical errors should be the top priority for research and resources.  However, information with regards to death caused due to medical errors is not easily available.  The CDC (Centers for Disease Control and Prevention) uses death certificates to rank causes of death and accordingly establish health priorities.  The cause of death as stated on the death certificate is based on the ICD (International Classification of Diseases) code, which unfortunately does not have any code attached to human or system errors.  Given the fact that 117 countries use the ICD system to code their death certificates and use the resultant data as the primary health status indicator, we can begin to see how difficult it is to collate data regarding death due to medical errors.  It should be remembered that the medical coding system was originally designed to help physicians with their billing and not for collecting health data.  Using data collected from this system to prioritize health status does leave room for error.

How would anyone benefit from knowing the numbers related to death due to medical errors?  Public health priorities and research funding are based on data released by the CDC, stating top ranked causes of death in the country.  Hence, heart disease and cancer, being the top two ranks in causes of death, receive tons of funding and attention, resulting in further research and improvements in trying to reduce their incidence.  Since data regarding death caused due to medical errors does not feature on any recognized and standardized method of collection, the incidence rates in this case have never been a part of the health status priority.  But, if the report is any indicator on the gravity of this issue – death caused due to medical errors should feature on the health status priority list and immediate steps should be taken to create strategies for reducing it.

According to the CDC, heart disease claimed 611,105 lives, 584,881 died due to cancer and 149,205 lives were lost to chronic respiratory disease in the year 2013.  However, examining four studies that analyzed data from 2000 to 2008 on the death rates and using hospital admission rates from 2013, the authors extrapolated that based on the 35,416,020 hospital admissions, 251,454 deaths resulted due to medical errors.  This puts death due to medical errors at 9.5% of all deaths each year and makes it the third leading cause of death in the US.

Suggesting several changes that include making errors more visible, for example by adding them as a reason in the death certificates, would help in understanding and reducing this problem, according to the authors.  Hospitals need to carry out quick and efficient investigation to determine if medical errors played any role in the death of the patient, suggested the authors, adding that there should be a standardized data collection system related to death caused due to medical errors to help build an accurate picture for prioritizing this problem.

According to the authors, “Human error is inevitable, but we can better measure the problem to design safer systems mitigating its frequency, visibility and consequences.  Most errors are not caused by bad doctors but by systematic failures and should not be addressed with punishment or legal action.”


  1. Frellick, M. (2016, May 03). Medical Error Is Third Leading Cause of Death in US. Retrieved May 05, 2016, from
  2. Martin A Makary, p. M. (2016, May 03). Medical error—the third leading cause of death in the US. Retrieved May 05, 2016, from