State of New Hampshire v. Witty (unreported, November 25/15, New Hampshire Superior Court, Southern District, Docket No. 226-2014 CR-00568) is an interesting case wherein the state sought to lead vehicle speed determination evidence premised on problematic surveillance video without the use of an expert witness. The defense sought to exclude this evidence.
The relevant facts were that a fatal motor vehicle collision occurred at an intersection and it was alleged that the defendant was at fault for the collision as a result of him failing to stop for a red light. Surveillance video that purportedly showed the collision and the color of the traffic lights at relevant times was obtained from a nearby business.
The original video from the business’s server was not preserved and therefore the only version available was the copy obtained by the police. It could not be determined if that copy was a faithful copy of the original. The time stamp on the video indicated that a new image was captured every second. The time stamp recorded only seconds, not fractions of a second.
A police officer with no training or experience in forensic video analysis purported to conduct a speed analysis from the video evidence, while acknowledging that he did not know whether the time stamp was accurate. Further, there was no evidence that the time stamp advanced at intervals that were uniform and precise or that it correctly corresponded to the change in image.
The defense brought a pre-trial motion to exclude or restrict the use of the video evidence at trial. The defense argued that the state provided no evidence as to the accuracy and reliability of the time stamp, expert or otherwise, and further, that since the original video was no longer available, this was something that could no longer be determined. The defense argued that the time stamp should be redacted from the video evidence used at trial and that the state should be prohibited from using the video to determine vehicle speed. Using a Rule 403 analysis, the defense argued that the danger of misuse of the video evidence to determine speed outweighed the probative value of the video evidence. Specifically, the concern expressed was that leaving the time stamp on the video might cause the jury to conduct their own speed analysis, utilizing a time stamp that had not been proven to be authentic, giving rise to unfair prejudice.
Following the presentation of evidence from the defense forensic video analysis expert, the state agreed to redact the date and time stamp and agreed that the video could not be reliably used to determine vehicle speed. However, the state argued that the video was relevant for other purposes such as determining vehicle position and movement and that it should be ruled admissible for those limited purposes.
The Court found that the video evidence had probative value as it corroborated certain aspects of eyewitness testimony and also depicted the moment when the defendant swerved to the left, indicating when he became aware of the impending hazard. As to prejudicial value, the Court stated:
The recording is not, however, without prejudice. By playing the recording as a video, the jury may attempt to determine the speed of the defendant’s truck, his stopping distance, and when he first braked despite the fact that the video is not reliable for those purposes. Additionally, because of the way the video advances its frames, it can lead to a highly distorted perception of the length of time the defendant had to brake before entering the intersection.
The Court ruled that the state was not permitted to show the video evidence as a moving video for the prejudicial reasons noted above. However, the state was permitted to use still images taken from the video as those images would show the things the state wanted to jury to see without creating an opportunity for the jury to misuse the video evidence to calculate vehicle speed.
According the defense motion was effectively granted.
This in limine motion has no precedential value but it does provide some valuable teaching points.
First, when relying on video evidence, the original video should be preserved for future use and for examination by experts for both parties in the litigation. Where it is not possible to preserve the original video, the copy that is exported must be confirmed to be a faithful replication of the original media.
Second, in order for speed calculations to be determined from video evidence, it must first be established that the date and time stamp is both accurate and reliable. In other words, the video evidence must be authenticated. For more information on authentication and date and time stamp accuracy, refer to other articles found at www.jonathanhak.com.
Third, attempting to determine an accurate vehicle speed from video with a reduced frame rate and a time stamp that does not show fractions of a second is fraught with reliability challenges. These challenges must be fully explored by appropriately qualified experts and counsel so that the evidence provided to the court is presented in its true light.
Fourth, expert witnesses are required in order to conduct a proper analysis of vehicle speed from video evidence. Triers of fact should not be placed in a position where they are given the raw data to do their own calculations and the parties hope they get it right. This is an area where the trier of fact is in need of expert assistance.
Determining the speed of vehicles observed on video requires reliable, accurate video with a suitable frame rate. Further, properly trained video experts are required in order to properly interrogate and interpret the video evidence, together with a collision reconstruction expert to apply the data to the events depicted.