The trial judge presiding over the Aaron Hernandez murder trial in Fall River has just reversed a critical decision she made on Wednesday that could have been fatal to Hernandez’s case. During trial on Wednesday, the prosecution called an employee of the gun manufacturer Glock to testify about home surveillance footage taken in Hernandez’s home only minutes after the murder of Odin Lloyd. My Fox Boston reported on the events.
The footage revealed an unclear depiction of Hernandez walking through his home at 3:30am carrying a black object that resembled a gun of some sorts. The prosecutor asked the witness whether he recognizes the object, and the witness testified that the object looked identical to what he recognizes from his experience as being a Glock 21. And although the defense attorneys attempted to strike that testimony from the record, the trial judge decided that the testimony was permissible. This testimony is arguably the most fatal part of Hernandez’s defense, since it connects Hernandez to the alleged murder weapon at the time of the crime.
The Rule: Lay vs. Expert Witnesses
There was at least one major problem with the court’s ruling on this testimony. The witness who testified was never “qualified” or “certified” as an expert witness. Instead, he was simply testifying as a “lay” witness. The distinction is critical because lay witnesses are much more limited in their testimony than expert witnesses. The rules of evidence do not permit a lay witness to render an opinion about an area of expertise – such as gun models and component parts. A lay witness is only allowed to testify as to his observations or knowledge of facts, and may only state opinions that are common knowledge to any reasonable person. An expert, however, is allowed to render a scientific opinion or an opinion based on specialized knowledge, as long as the opinion is found by the trial court to be relevant and reliable as based on actual science. The court would ordinarily conduct what is called a “Daubert Hearing” to determine whether the expert could give any particular opinion testimony; this hearing is conducted outside the jury’s presence.
The witness in the Hernandez trial who stated an opinion that the surveillance image did in fact depict a Glock 21 was never qualified as an expert – for one reason or another. Therefore, he can only testify as a lay witness, and so may not state an opinion based on any scientific or specialized expertise – even if he actually does possess such expertise. In this case, the witness was an employee of the gun manufacturer, and during his testimony he described the component parts of a Glock 21, and identified those parts for the jury in the surveillance video depicting Hernandez. The witness then explicitly stated that it was his opinion that Hernandez was carrying a Glock 21 in the video. This testimony is impermissible because it now exposes the jury to what is possibly unreliable testimony, which could influence the jurors and taint their verdict.
Grounds for Appeal
The trial judge ultimately recognized her mistake and returned to court the next morning reversing her decision and instructing the jurors to disregard that portion of the witness’s testimony. A problem for Hernandez remains however. Even though the court specifically instructed the jurors to disregard the testimony, it is highly impractical to ask someone to forget something they have just heard and has so much significance to them – especially when you remind them of the statements that are to be forgotten. The fact that such an enormous mistake was made by the trial judge gives the defense attorneys a substantial basis to appeal the case should Hernandez be convicted. The defense may ague on appeal that the jury’s thoughts were permanently and fatally tainted by the improper testimony, because there is a high probability that the jury was influenced by the testimony. Whether this argument would succeed, however, depends on the strength of the remainder of the case.