A recent example is U.G. v. United States, 2022 WL 7426212 (S.D.N.Y. Oct. 13, 2022), a medical malpractice action under the Federal Tort Claims Act in which plaintiff suffered a shoulder injury during his birth and was later diagnosed with permanent Erb’s palsy, or brachial plexus injury.  He alleged that the obstetrician caused the injury by using excessive force on his head and shoulders during delivery.  In support of his claims, he offered two causation experts – an obstetrician/gynecologist and a pediatric neurologist– both of whom claimed the “totality of the circumstances” ruled out several possible alternate causes and thus showed that the defendant caused the injury.

Their problem?  Both dismissed the possibility that natural birth forces caused the injury.  But a monograph from the American College of Obstetricians and Gynecologists (ACOG), widely accepted in the field and endorsed in a number of court decisions, specifically stated that brachial plexus injuries are known to occur for reasons unrelated to a physician’s application of force.  Plaintiff’s experts admitted that normal labor forces could cause transient injuries but argued they could not cause permanent injuries such as those experienced by plaintiff.  However, the ACOG monograph concluded that “persistent” injuries could be caused by normal labor forces, stating that “[n]o published clinical or experimental data exist to support the contention that the presence of persistent (as opposed to transient) [brachial plexus injuries] implies the application of excessive force by the birth attendant.”  Defendant also cited two other peer-reviewed publications that likewise indicated normal labor forces could cause brachial plexus injury.

Plaintiff attacked the ACOG monograph, arguing that “persistent” injuries as described in the monograph are different than “permanent” injuries, but the ACOG definition of persistent – a condition lasting 12 months or more after birth – was consistent with plaintiff’s experts’ definition of a permanent condition as one lasting beyond one to two years of a child’s life.  Plaintiff also argued the monograph’s conclusion was supported by only a single article he said was unreliable.  But the monograph cited that article only as an example, not as the sole support for its conclusion, and plaintiff had failed to challenge the remaining articles – or, indeed, the other literature defendant had cited in challenging the experts.   Having made these observations, the court then cited a number of other courts that had likewise found the ACOG monograph to reliably establish that brachial plexus injuries could be caused by forces of labor alone.

Plaintiff further argued that the experts had ruled out several other possible causes of the injury, but the court observed that both experts based their opinions on the idea that normal labor forces cannot cause permanent brachial plexus injury.  Because that premise was “simply not supported by the scientific literature,” the court excluded the experts’ opinions as unreliable ipse dixit.    

Challenging an opposing expert’s opinions as unreliable is no small task.  One must convince the court that the expert, who has an advantage in terms of familiarity with the field, has ignored or misapplied principles and methods that may be completely foreign to the court.  As U.G. illustrates, literature can level the playing field.  It can arm the court with a scientific consensus on a key issue, helping it to discharge its gatekeeper duty without undue deference to the proffered opinions based on the witnesses’ general expertise in the relevant field.  This opinion shows how key literature that is widely accepted in that field and relied on by other courts can lead to victory on a motion to exclude.