In Maryland, Arthur Carroll and Kevin Jackson went to Nathaniel Marr’s home to commit a robbery. While searching Marr’s home, Carroll and Jackson shot and killed Ronald Muse, Marr’s cousin. Marr later went looking for Carroll and Jackson, allegedly to talk about Muse’s murder. Marr saw Carroll walking toward a waiting taxi. Carroll grabbed at Marr’s waist, and Marr fired shots, claiming that he feared for his life. One of the bullets entered the taxi and struck Jimmy Abass, the driver. Marr was charged with the murder of Carroll and the first-degree assault of Abass. In a statement to the police, Marr said that he was scared when he heard about Muse’s death and was armed when he approached Carroll in order to protect himself. At trial, the court instructed the jury on the defenses of perfect and imperfect self-defense. Marr requested additional instructions for the jury to judge the reasonableness of Marr’s actions based on the facts as they appeared to Marr at the time of the events. The trial court refused to give the additional instructions. Marr was convicted. Marr appealed, arguing that the trial court erred in refusing the instructions. Maryland’s intermediate court of appeals held that the refusal constituted reversible error.