As exemplified by a recent decision by the Supreme Court of Pennsylvania, the current trend is to allow computer-generated animation (CGA) for demonstrative purposes.
In the case of the Commonwealth of Pennsylvania v. Serge, the defendant was arrested and charged with the murder of his wife. She had been shot three times and killed inside their house. The commonwealth filed a motion with the trial court seeking to present the prosecution's theory of the fatal shooting through a CGA based on both forensic and physical evidence.
A CGA is a series of drawings created by a computer that, when assembled frame-by-frame, produce an image of motion. The image is a graphic representation depicting previously formed opinions of witnesses. Thus, a CGA is only as reliable as the underlying testimony it seeks to represent. Unlike a computer-generated simulation, a CGA does not calculate an outcome or come up with a conclusion.
The trial court granted the motion, allowing the CGA into evidence and requiring that it be a fair and accurate depiction of expert reconstructive testimony and that it not include any inflammatory features that could cause unfair prejudice.
During the jury trial, the defendant alleged that he had acted in self-defense when his wife had supposedly attacked him with a knife. The commonwealth responded that the killing was intentional by the defendant and that he had used his prior experience as a police officer to tamper with the crime scene to stage a self-defense setting. Specifically, the commonwealth argued that the defendant had moved his wife's body near a knife that he placed on the floor. This was depicted in the CGA. The CGA also portrayed the commonwealth's theory that the defendant had shot his wife in the lower back and then through the heart as she knelt on the living-room floor of their home.
At the end of the trial, the jury found the defendant guilty of first-degree murder and he was sentenced to life imprisonment. The defendant appealed, and argued that the trial judge improperly had admitted the CGA into evidence.
The Supreme Court of Pennsylvania determined on appeal that the CGA was properly admitted into evidence because its probative value outweighed any prejudicial impact. In coming to this conclusion, the court announced some broad-minded principles: "Society has become increasingly dependent upon computers in business and in our personal lives. With each technological advancement, the practice of law becomes more sophisticated, and commensurate with this progress, the legal system must adapt. Courts are facing the need to shed any technophobia and become more willing to embrace the advances that have the ability to enhance the efficacy of the legal system...This is, after all, the 21st century."
Here the Supreme Court believed that the CGA was appropriate as a matter of evidence because it helped to educate the jury, it was supported by the underlying testimony of witnesses, and because it was not unfairly prejudicial to the defendant. The court noted the defense argument that a CGA has the potential to unduly influence a jury because of its visual impact, but swept that argument aside, relying on a controlled study that suggests that CGAs have negligible measurable impact upon juries when the CGAs do not present new information. Furthermore, the CGA in this instance was devoid of drama or bloody details, and the defense was able to ask cross-examination questions designed to undermine the credibility of the CGA.
Technology likely will continue to invade courtrooms across the country. While this can be helpful, we must be vigilant to ensure that technological representations of reality are supported by accurate testimony and physical evidence, and that the value of any inflammatory representations is not outweighed by their visual and potentially shocking effect.