On April 21, 2015, in Standley v. Edmonds-Leach, the US Court of Appeals for the District of Columbia Circuit clarified the test for determining admission of witness testimony under FRCP 26(a)'s impeachment exception (No. 13-7104, (D.C. Cir. Apr. 21, 2015)).

Plaintiff Melissa Standley brought tort claims against the District of Columbia and D.C. Public Library Special Police Officer Karen Edmonds-Leach after an altercation in a D.C. public library. At trial, defendants sought to call Wendell Kellar, a library employee who witnessed the altercation, as a witness. Standley objected on the ground that the defendants knew about Kellar and his knowledge of the incident during discovery but failed to identify him as a potential witness pretrial as required by FRCP 26(a).

FRCP 26(a) requires initial disclosures, including the name and contact information of each person likely to have discoverable information that the disclosing party may use in the action. There is an exception for information that the party would use "solely for impeachment" (FRCP 26(a)(1)(A)(i)). Additionally, a party must identify every witness that it may call "other than solely for impeachment" (FRCP 26(a)(3)(A)(i)). A party may not call a trial witness who it failed to identify in violation of Rule 26 unless the failure was "substantially justified" or harmless (FRCP 37(c)(1)).

The district court allowed Kellar to testify as an impeachment witness, holding that he was "not called solely for corroboration." Kellar testified about two areas of impeachment, as well as a third matter that had no impeachment purpose and served only a corroborative function. The jury returned a verdict in the defendants' favor. The district court entered judgment for the defendants.

Standley appealed. She asserted that Kellar's testimony was not offered "solely for impeachment," as FRCP 26(a)'s exception to witness disclosure requires. That error prejudiced her because Kellar was the only non-party witness and she had not been able to obtain discovery from him.

On appeal, there was no dispute that Kellar's testimony was admissible at trial only if it was subject to FRCP 26(a)'s "solely for impeachment" exception. The DC Circuit noted that courts have split over how to interpret the impeachment exception.

Some courts have concluded that the impeachment exception is limited to evidence that has no potential utility other than impeachment. Other courts have held that parties may present at trial undisclosed evidence with both impeachment and substantive qualities if they use it strictly to impeach. Under both views, courts have focused on the word "solely."

In this case, the district court ruled that Kellar could testify because he was "an impeaching witness and not called solely for corroboration." The DC Circuit clarified, however, that under FRCP 26(a) the question is whether the testimony will be used "solely for impeachment," not whether it will be used solely for corroboration. By shifting the critical word "solely" to modify "corroboration" rather than "impeachment," the district court applied the wrong test in deciding whether to admit Kellar's testimony.

The DC Circuit explained that because it misstated the applicable standard, the district court failed to address the considerations that other circuits found relevant when applying FRCP 26(a)'s impeachment exception. Given the district court's legal error, and because it was not clear that Kellar's testimony would have been admissible under either interpretation of FRCP 26(a), the DC Circuit did not choose between the competing approaches to the "solely for impeachment" exception.

Rather, concluding that the error was not harmless, the DC Circuit reversed and remanded the matter for a new trial without Kellar's testimony.