In the Law.com article “Order Tossing Expert Grabs Attention in Asbestos Case” it is reiterated that an expert witness must not “advocate” for a particular side but must be a “dispassionate scientist/witness.”

    “For the reasons stated in the defendant’s brief, the court finds that Dr. Maddox easily qualifies as such a ‘quintessential expert for hire’ not only for the length, frequency and apparent lucrativeness, but also the litigation orientation he exhibited in attempting to add a proper empirical basis for his opinion after he had originally stated his sworn opinion and the court first found that it was inadmissible.

This transgressed the scientific rule that the empirical data should lead to the theory, not vice versa. Although no person probably enjoys seeing their testimony discounted, during his live testimony at the hearing on this motion, Dr. Maddox’s behavior seemed much more consistent with an advocate than a dispassionate scientist/witness,” Parrott said in the order.

This opinion was formed during the “Daubert hearing” that lasted the whole day.

In addition to the 1993 Supreme Court’s decision in Daubert v. Merrell Dow Pharma, the judge also cited a 1996 decision from the 7th U.S. Court of Appeals saying “the courtroom is not the place for scientific guesswork, even on the inspired sort,” and the 2005 Georgia Law governing the use of expert witnesses saying the opinion “is not practically testable and has not been tested.”

The judge also speaks to the “expert for hire” issue. A full-time expert witness seems to always carry this stigma. A professional practitioner who also serves as an expert in a few cases, and who draws only a portion of his fees from expert testimony seems to be more acceptable to judges and juries.

What percentage I guess is based on the opinion of the judge. But, you can bet, that the Daubert hearings will increase because of this and other cases of late.