There is a familiar refrain commonly heard in medical malpractice actions that a departure from the standards of accepted medical practice may not be established based upon hindsight. This is simply another way of stating that the determination of whether a physician was negligent must be based upon the circumstances that existed at the time of the subject care or treatment. However, the rule prohibiting hindsight is often the subject of misapplication and misuse.

Facts or conditions that develop or become manifest after the alleged malpractice may be highly relevant and perfectly appropriate in determining whether there was a departure from the standards of care. For instance, if surgery is performed on a patient, and the patient is subsequently found to have a sponge at the location of the surgical site, it may be logically deduced from that subsequently disclosed condition that the surgeon departed from accepted practice by leaving the sponge inside the patient during the surgery. This is circumstantial evidence in its purest form.