People v. McDonald

Eddie McDonald (defendant) was charged with murder for the 1979 shooting of Jose Esparza. Before trial, McDonald moved to introduce expert testimony regarding the reliability of eyewitness identification. Dr. Robert Shomer, a practicing psychologist and psychology professor, would have (1) explained various psychological factors that may impact the reliability of eyewitness identifications and (2) countered some common misunderstandings about how people perceive events, store memories, and retrieve memories. The prosecution (plaintiff) conceded that Shomer was qualified to testify as an expert but otherwise opposed the motion. The trial court excluded Shomer’s testimony, reasoning that Shomer’s testimony would invade the province of the jury and was not scientific enough to be admissible. At trial, the only evidence incriminating McDonald was four eyewitnesses’ identifications of McDonald as Esparza’s shooter, and each identification had weaknesses. Another prosecution eyewitness testified that McDonald was definitely not the shooter. Six defense witnesses testified that McDonald was in Alabama on the day that Esparza was murdered. The jury convicted McDonald, and McDonald was sentenced to death. McDonald appealed to the California Supreme Court, primarily arguing that the trial court had erred by excluding Shomer’s testimony.