by Nadine Nasser Donovan, Esq.

Medical malpractice actions are unusual in that many states require patients (i.e. plaintiffs) to demonstrate that they have expert witness support for their medical malpractice allegations before suit is filed. Such requirements are grounded in either state statutes or regulations. These rules are designed to discourage frivolous malpractice lawsuits and encourage pre-suit settlements of claims. In essence, the rules won’t allow a medical malpractice case to go forward unless a doctor has signed a statement under oath offering an expert opinion that the case has merit, otherwise known as an affidavit of merit.

What is an affidavit of merit? Definition and Contents

An affidavit of merit is a statement of counsel or the medical expert under oath attesting to the merits of the plaintiff’s malpractice lawsuit. More than half of U.S. States require filings of affidavits of merit. The content and level of detail required in such affidavits vary from jurisdiction to jurisdiction.

A typical affidavit of merit in a medical malpractice could consist of:

  • Statement of the plaintiff expert witness’s qualifications.
  • Statement that the plaintiff expert physician is familiar with standard of care in question.
  • Expert has determined that the defendant’s conduct did not meet the appropriate standard of care.
  • That failure caused the plaintiff’s injury.

How to Write an Affidavit of Merit

You will want to do so very carefully, as you are signing the statement under oath on which you can be questioned in the future in this case or any other. Closely study the medical records of the plaintiff. Do not rely solely on representations of plaintiff’s counsel about what happened – “trust but verify.” Review all other available records. Do not let counsel cherry pick what records you see and what records you don’t see. If applicable, do the necessary medical research. Do not offer written opinions or sign off on pre-suit opinions (even in a general fashion) until you have formed your opinion to a reasonable degree of medical certainty.

It is common practice for retaining counsel (the plaintiff’s lawyer) to take a first shot at drafting the affidavit of merit. In such cases the expert will want to take an active role in studying and revising the draft. It is good practice of course to have a detailed conversation with retaining counsel before the first draft is created. This will save time and help avoid miscommunications. The affidavit is a statement made under oath.  It is critical that the expert understand and agree with every word in the affidavit – including all “legalese.”


Learning how to write an affidavit of merit at a high level is critical for expert witnesses involved in medical malpractice cases. The reputation of both the expert witness and the defendant provider are at stake in the process. Do your homework, be honest, and make sure you agree with and understand with every single word in the affidavit.


Nadine Nasser Donovan, Esq. is the Lead Trainer/Consultant of SEAK, Inc. – The Expert Witness Training Company. Nadine is a former medical malpractice defense attorney with extensive litigation experience. She is the creator of and presenter for SEAK’s highly acclaimed CME streaming course How to Excel as an Expert Witness in Medical Malpractice Cases. Nadine works 1-1 with medical experts in malpractice cases to prepare them for deposition and trial and help them draft superior reports. She received her J.D. cum laude from Boston College Law School. She graduated from Fordham University summa cum laude with a B.A. in French Literature. Nadine can be contacted at 617-791-4282 or