U.S. Supreme Court

Case Status


Docket Number



Cert. Denied


Questions Presented

The question posed in this case is whether a district court abuses its gatekeeping discretion under Daubert in concluding that an expert cannot testify based on his ipse dixit opinion as to the weight of the scientific evidence when that expert provides no testable methodology for his claimed balancing of different pieces of scientific evidence, each of which individually are also not derived by the scientific method.

Case Updates

Cert. petition denied

January 09, 2012

U.S. Chamber urges Supreme Court to review expert witness testimony and sound science decision

October 13, 2011

NCLC urged the Supreme Court to review a decision by the First Circuit that threatened to undermine Supreme Court precedent requiring that expert testimony be admitted only when it is based on sound science. In this case, the district court ruled that an expert witness could not offer testimony that was based on his own personal opinion about the weight of the evidence, where that expert provided no testable scientific methodology supporting his testimony. The First Circuit held the district court’s refusal to admit this testimony to be an abuse of discretion. NCLC’s amicus brief argued that the First Circuit’s decision threatens the viability of the Supreme Court’s decisions in Daubert v. Merrell Dow Pharms., Inc., 509 U.S. 579 (1993) and General Elec. Co. v. Joiner, 522 U.S. 136 (1997), which established necessary safeguards to protect against admission of scientifically unreliable expert evidence. This ruling threatens to subject businesses to litigation in cases where there is no sound scientific rationale for holding the company liable.

Case Documents