Experts can be cross examined on their personal practices
A new Illinois medical malpractice case settles once and for all a common problem that arises at trial. I have frequently obtained admissions from defendant's experts as to their personal practices in caring for patients similar to my clients.
When I have tried to cross examine the expert on these personal practices at trial the defense attorney objects that his expert's personal practices are not relevant to the case -- only the standard of care is relevant. Judges vary on how they rule on this objection.
Schmitz v. Binnette resolves this issue in favor of the right of the cross examiner to challenge the credibility of a witness that claims a test or procedure is not standard of care but he still does it as a matter of routine.
The court held: As noted, when questioned by the defense about the indigo carmine dye test, Dr. Mercer explained several dangers of the test, including that it is an invasive procedure, that it increases the risk of infection, that there is a risk of lacerating the urethra, and that some patients may have allergic reactions to the dye. Dr. Mercer also stated that the test fails to identify an obstruction in 30% to 50% of cases. Thus, Dr. Mercer did not merely testify that the indigo carmine dye test was not required by the standard of care, he implied that the test was unreasonably dangerous and ineffective. This testimony would have been readily impeached had plaintiff been allowed to question Dr. Mercer about his personal practice of performing the indigo carmine dye test "quite regularly, quite commonly." Accordingly, we find that the trial court erred in barring plaintiff from questioning Dr. Mercer about his personal practices.
For the foregoing reasons, we reverse and remand for a new trial.
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