People v. Gil

--- N.Y.S.2d ---, 1998 WL 316150, 1998 Slip Op. 05969
(N.Y.A.D. 1 Dept, June 16, 1998)

Brief Filed: 7/97
Court: New York Supreme Court, Appellate Division
Year of Decision: 1998

Read the full-text amicus brief (PDF, 229.52KB)


Whether cognitive research evidence and expert testimony regarding laypersons' beliefs concerning physics was admissible in a murder trial

Index Topics

Expert Witnesses/Psychologists' Competency; Scientific Research


Defendant was convicted in a jury trial of manslaughter in the second degree for tossing a bucket off the roof of his apartment building to the empty sidewalk below in an effort to distract police officers farther down the street who were arresting people in his neighborhood. The bucket traveled horizontally for thirty-five feet and hit and killed a police officer. Defense counsel averred that defendant had no criminal record, was an otherwise model citizen, and had intended simply to create a diversion. He tested at an IQ between 67-72 and was allegedly unable to perceive the risks involved in his conduct. Because of this, counsel urged that he be convicted of criminally negligent homicide rather than murder or manslaughter in the second degree. The prosecutor argued that the jury should infer that because the bucket landed in the street, thirty-five feet from the building, the defendant intended to throw it onto the crowded street and not the empty sidewalk, thus evidencing depraved indifference to human life and conscious disregard of the risks involved. In order to rebut this argument, defense counsel sought to introduce the expert testimony of a cognitive psychologist, specializing in intuitive physics — the study of misconceptions of the basic laws of physics. The psychologist proposed to testify that the inference urged by the prosecution was based upon the misconceptions lay people harbor regarding the basic laws of physics — particularly, the horizontal motion of falling objects. Specifically, the proffered testimony was offered to show that most people do not understand the laws of physics, do not anticipate the continuous horizontal motion of falling objects, and are unaware of these misconceptions. The testimony was excluded over defense objections and that exclusion became one basis for appeal.

APA's Position

APA submitted an amicus brief in support of the defendant arguing that: (1) the proffered testimony was highly relevant to the issue before the jury since studies in intuitive physics demonstrate that people regularly underestimate the distance that falling objects will travel horizontally, and since evidence in intuitive physics would have tended to prove the defendant's claims and to disprove the prosecution's theory of the case; (2) the proffered testimony is generally accepted as reliable by the scientific community and thus satisfies the Frye test (used in New York) for the admissibility of scientific evidence; and (3) studies in the area of intuitive physics demonstrate that people's lack of understanding of the laws of motion are clearly beyond the knowledge of the ordinary juror.


The New York Supreme Court, Appellate Division, unanimously affirmed the lower court's holding. The court rejected the APA arguments regarding the cognitive research evidence and held that the lower court permissibly exercised its discretion in excluding the proffered testimony on general misconceptions about the laws of physics "where the issue of defendant's mental state when he threw a heavy bucket off a roof, resulting in the death of a police officer, was a factual and credibility issue that the jury could evaluate without the proposed expert testimony." The court noted that defendant had been permitted to offer the testimony of both a physics expert and the examining psychologist who stated his opinion regarding the defendant's ability to appreciate the risk involved in his actions. Additionally, the court found that the testimony, even if admitted, would not have changed the jury's manslaughter verdict since there was ample evidence of recklessness in defendant's own contention.