Cite as: 522 U. S. 136 (1997)
Breyer, J., concurring
sufficient, whether individually or in combination, to support their conclusions that Joiner's exposure to PCB's contributed to his cancer, the District Court did not abuse its discretion in excluding their testimony. These conclusions, however, do not dispose of this entire case.
Respondent's original contention was that his exposure to PCB's, furans, and dioxins contributed to his cancer. The District Court ruled that there was a genuine issue of material fact as to whether Joiner had been exposed to PCB's, but concluded that there was no genuine issue as to whether he had been exposed to furans and dioxins. The District Court accordingly never explicitly considered if there was admissible evidence on the question whether Joiner's alleged exposure to furans and dioxins contributed to his cancer. The Court of Appeals reversed the District Court's conclusion that there had been no exposure to furans and dioxins. Petitioners did not challenge this determination in their petition to this Court. Whether Joiner was exposed to furans and dioxins, and whether if there was such exposure, the opinions of Joiner's experts would then be admissible, remain open questions. We accordingly reverse the judgment of the Court of Appeals and remand this case for proceedings consistent with this opinion.
It is so ordered.
Justice Breyer, concurring.
The Court's opinion, which I join, emphasizes Daubert's statement that a trial judge, acting as "gatekeeper," must " 'ensure that any and all scientific testimony or evidence admitted is not only relevant, but reliable.' " Ante, at 142 (quoting Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U. S. 579, 589 (1993)). This requirement will sometimes ask judges to make subtle and sophisticated determinations about scientific methodology and its relation to the conclusions an expert witness seeks to offer—particularly when a case arises in an area where the science itself is tentative or
147
Page: Index Previous 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 NextLast modified: October 4, 2007