David Patrick Ramirez (defendant) had a confrontation with another man named David, who visited Ramirez’s girlfriend while Ramirez was present at his girlfriend’s townhouse. After letting David into the house, Ramirez threatened David, pressing a gun against David’s side. One month later, Ramirez walked out of the townhouse and saw David’s brother, who looked like David, walking toward him. Ramirez shook the brother’s hand, then suddenly pulled a gun and shot and killed the brother, pausing between the second and third shots. The sole issue at Ramirez’s trial was whether the murder of David’s brother was premeditated. (Ramirez argued that the shooting was impulsive.) An Arizona statute defined premeditation as an intentional or knowing killing of a human being preceded by a “length of time to permit reflection.” A.R.S. § 13-1101(1). The court instructed the jury as follows: premeditation “means the defendant’s knowledge that he will kill another person existed . . . long enough to permit reflection. [T]he time for reflection must be longer than the time required merely to form the knowledge that conduct will cause death. It may be as instantaneous as successive thoughts in the mind. . . . It is this period of reflection, regardless of its length, which distinguishes first . . . from second degree murder.” The jury found that the murder was premeditated and convicted Ramirez of first-degree murder. Ramirez appealed, arguing that the court’s instruction to the jury lessened the state’s burden to prove premeditation for first-degree murder.