In People v. Hall (1983) 35 Cal.3d 161, defense counsel requested an explanation for the prosecutor's peremptory challenge of four or five jurors. The trial court denied the motion, saying the defendant had not shown all Blacks had been excluded and the court may accept the prosecutor's reasons even though they appear disingenuous. (Ibid.) The Supreme Court reversed, holding that if a prima facie case of group bias is shown, the prosecutor must come forth with an explanation for exercising the peremptory challenge that the court believes is genuine. (Id. at p. 167.) This requires a sincere and reasoned attempt to evaluate the prosecutor's explanation in light of the circumstances of the case, knowledge of trial techniques, and the manner the prosecutor has examined the jury and exercised challenges. (Id. at pp. 167-168.)