Computerized Accident Reconstruction Held Inadmissible

The Court of Appeals of Washington has ordered a new trial in a criminal case in which the State admited into evidence computer-generated simulation evidence using Version 6.2 of a program called PC-CRASH to prove that defendant had been the driver of the vehicle involved in the wreck.

The Court held that “we cannot be confident that a scientific consensus has been achieved among accident reconstructionists that PC-CRASH is capable of accurately performing the predictions to which the State’s expert witness testified.” Therefore, the Court reversed a jury verdict against the defendant and remanded the case for a new trial.

More specifically, the Court said that “[j]urisdictions that have addressed the issue uniformly hold that the admissibility of computer-generated models or simulations (as opposed to animations) as substantive proof or as the basis for expert testimony regarding matters of substantive proof is conditioned upon a sufficient showing that (1) the computer is functioning properly; (2) the input and underlying equations are sufficiently complete and accurate (and disclosed to the opposing party so that they can be challenged); and (3) the program is generally accepted by the appropriate community of scientists for use in the particular situation at hand. [Citations omitted.] We agree with these courts, and hold that in Washington, computer-generated simulations used as substantive evidence or
as the basis for expert testimony regarding matters of substantive proof must have been generated from computer programs that are generally accepted by the appropriate community of scientists to be valid for the purposes at issue in the case.”

The State used the evidence to prove that the defendant was driving the vehicle and the Court held that “we cannot countenance the State’s use of such evidence here or in future cases and that will remain true until such time as the State demonstrates that the relevant scientific community has reached consensus with respect to the validity and reliability of the PC- CRASH program used by Heusser, for the specific purposes here at issue.” The Court noted that in another case “the PC-CRASH program was used to predict movement of the vehicle in a single-impact crash, and the relevant scientific community of accident reconstructionists agreed that
the computer program was reliable for that purpose” but noted that the program was being used for a different purpose in this case.

Of course, this is a criminal case. but the evidentiary principles are the same as they would be in a civil case.