Motion to Exclude Improper Opinion Testimony on Manner of Death

This motion argues for the exclusion of opinion testimony by medical examiners on the manner of death in a homicide trial under both the rules of evidence and the Sixth Amendment jury trial right. It explains that medical examiners speculate as to the “manner” of death based on extraneous information provided to them, notes that these determinations are not based on science, and emphasizes that there is “no standardized or validated system” for making these judgments (pages 18-23). The motion also cites cognitive science in support of the claim that biases, including racial biases, can shape these “manner of death” determinations (pages 23-24). Attached to the motion are (1) transcripts of interviews with two medical examiners, exposing the problems with manner of death determinations; (2) an expert report and law review article detailing the cognitive science problems with these determinations; (3) the non-scientific manual used to instruct medical examiners on how to make these determinations; and (4) a letter signed by 86 forensic pathologists and death investigators about judicial misuse of manner of death determinations.