The People of the State of Colorado v. Ruben Rosendo Ramos

Summary

The court held that a police detective’s opinion distinguishing blood cast-off from blood transfer was expert testimony because an ordinary person would not reliably possess the experience or knowledge needed to make that distinction. The trial court therefore abused its discretion by admitting the testimony as lay opinion, and the court affirmed the court of appeals. Justice Coats, concurring in the judgment, agreed that admission was erroneous because the detective relied on training and experience, while Justice Boatright, dissenting, would have treated the testimony as lay opinion.