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Case Name: Thomas v. City of Chattanooga (Click here for the full text of the case)

Court: United States Court of Appeals for the 6th Circuit; on appeal from District Court for the Eastern District of Tennessee at Chattanooga

Date: February 9, 2005

Expert: Phillip Davidson, career in police training and operations

Issues: Did the district court err in concluding that the expert’s opinion was unreliable because it was conclusory

Summary of case: The plaintiffs sued the City of Chattanooga under a municipal liability theory after one of the plaintiffs was shot in his home by a Chattanooga police officer. Following an internal investigation, the Chattanooga Police Department found the shooting to be justified. The plaintiffs sued, claiming that the Police Department had an unwritten policy and practice of condoning the use of excess force by police officers.

Role of the expert: Davidson testified that the Chattanooga Police Department had an unwritten policy and practice of condoning excessive force, an inference he drew from, amongst other things, the number of complaints of excessive force made against the Department.

Challenges to the Expert's testimony: The district court found Davidson’s evidence to be unreliable and conclusory because Davidson had failed to provide the reasoning behind or basis for his opinion. Appealing the district court decision, the plaintiffs/appellants argued that Davidson’s testimony was non-scientific and so the traditional Daubert factors could not be applied to his testimony. They also argued that Davidson was entitled to draw upon his experience in forming his conclusion of an unwritten policy of excessive force. The Court of Appeals affirmed the district court decision, holding that Davidson could not just draw upon his experience, but was required to explain how he reached his conclusion. The Court of Appeals emphasized that Davidson had failed to conduct any kind of qualitative analysis of the cases of excessive force brought against the Department.

Summary prepared by R. Zapparoni