Police Expert Witness on Speed of Vehicle has Testimony Rejected


The court, in: IN THE MATTER OF THE COMPLAINT OF ANTILL PIPELINE CONSTRUCTION CO., INC. SECTION “C” (3), Civil Action No. 09-3646, Consol. Case No. 10-2633., United States District Court, E.D. Louisiana, dealt with the proposed testimony of a Lieutenant [ police expert witness] on the speed of a recreational vehicle.


The court rejected the testimony due to faulty methodology.


The court stated:


The Lieutenant [police expert witness] arrived at his opinion as to the recreational vessel’s speed through several steps. He first contacted a mechanic for a Yamaha dealer to download data from the recreational vessel’s engine. He then contacted an employee of an enterprise called Baggy’s Pro Shop, who provided him with a formula for converting the engine data (revolutions-per-minute or “RPMs”) into a speed. Finally, he plugged the data given to him by the Yamaha mechanic into the formula and arrived at a speed.


There are several problems with the Lieutenant’s methodology. First, he provides no evidence as to the technique used by Yamaha mechanic to extract the data from the vessel’s engine or that person’s competence to assess the technique’s reliability or proper execution. This seriously undermines the factual basis for his opinion. He likewise concedes that he himself is not familiar with the techniques for transforming engine RPM data into speed—indeed, he admits to relying on someone else (whose expertise in physics or engineering does not appear in the record) to provide him with the formula. Finally, it would appear that he may have made an arithmetic mistake in using the formula, which further calls into question the reliability of his opinion.


Accordingly, the Court concludes that it is inappropriate to qualify the Lieutenant as an expert witness. He did not gather the relevant facts (the RPM data from the recreational vessel’s engine), nor did he use his expertise to transform those facts into an ultimate opinion (the conversion of the RPM data into a speed). He simply relayed what he had been told by others, with no basis to assess its accuracy or reliability. And there is evidence that he made errors in his calculations.


It is immaterial that the Lieutenant was, as Antill urges, acting “within the course and scope of his employment,” which includes investigating boating accidents. Rec. Doc. 632 at pp. 1-2, 4-5. Investigating a death falls within the course and scope of both a police officer’s and a coroner’s employment. This does not render a police officer competent to testify as to matters of medicine anymore than the Lieutenant’s employment qualifies him as an expert in physics, engineering, or the performance of Yamaha motors on recreational vessels.


As the Court has determined that the Lieutenant’s calculation of speed should not be admitted because it is unreliable, it also concludes that the references to it in other experts’ reports should be excluded. While experts are allowed to rely on hearsay in forming an opinion, this exception may not be used to allow the introduction of evidence otherwise determined to be unreliable.