Is The Plural Of Email “Economic Evidence”?

The aphorism that the “plural of anecdote is data” is being put to the test in federal courts as judges grapple with the question of whether emails and other anecdotal evidence can form the basis of reliable expert economic opinion.

Recent federal court decisions concerning the type of evidence that may be relied upon by economic experts in formulating opinions indicate that the plural of email might just be “economic evidence.”

For example, in denying a motion to exclude plaintiff’s economist expert in Discover Financial Services v. Visa USA, Inc., 582 F. Supp.2d 501, 507 (SDNY 2008), United States District Judge Barbara Jones held that “qualitative” evidence, i.e., evidence that is not numerical or mathematical in nature, can be considered by an expert in rendering his or her opinion on market definition and power.  Anecdotal statements made in corporate documents – including e-mail – or deposition testimony are quintessential forms of qualitative evidence.

According to recent cases that followed Discover Financial, such evidence can support expert opinions as long as those opinions will “assist the trier of fact” under Fed. R. Evid. 702.  The best way to test whether the inferences that an expert draws from qualitative evidence are appropriate, according to these decisions, is through cross-examination at trial. 

Accordingly, parties to antitrust litigation should expect that party and non-party statements will be deemed evidence that can form the basis of reliable economic opinion.  Parties should not expect that an economic expert’s opinion must rely solely on quantitative or mathematical analysis.