Today Jammie Thomas filed her opposition to the plaintiffs' motion in limine to exclude her expert, University of Minnesota computer scientist Dr. Yongdae Kim. Thomas emphasizes that Kim's role is to rebut the opinions of plaintiffs' expert, and thus that it is permissible for him to posit "alternative explanations for the presence of KaZaA and certain alleged [sic] infringing songs on Defendant's computer." Kim will not, says Thomas brief, "offer an opinion on the probable cause of the presence of KaZaA and certain alleged infringing files" on Thomas' computer.
It's an uphill battle for the plaintiffs to win such a motion; I suspect the court will say: let both experts testify, and the jury will sort it all out. But the limited nature of Kim's opinions, as described in this brief, demonstrates a major problem with Thomas' case: she has no compelling affirmative version of events to tell the jury. While the burden is on the plaintiffs to prove their case, the jury will want the defense to do more than simply attempt to poke holes. They will want her (and her expert) to explain what actually did happen -- not merely offer theories, however implausible, as to what could have happened.
In the first trial, Thomas tried a blanket "I didn't do it" defense, bolstered by a "maybe somebody hijacked my wireless router" theory. The problem was, she didn't use wireless, and the jury didn't believe her. Whether Dr. Kim's additional 13 possible explanations can improve the credibility of Thomas' denials remains to be seen.