In what circumstances will the court allow appellant to argue that the jury selection system systematically excluded African-Americans?

Nor did appellant make any effort to show systematic exclusion. In the trial court, he asked the court to overlook this element of the requisite prima facie showing. On appeal, he argues, again without support, that "the undercounting of minorities and in particular African Americans presents a de facto systematic exclusion of this community group." Presumably appellant refers to the same study regarding undercounting. However, undercounting in some unspecified context does not begin to establish that the jury selection system systematically excluded African-Americans. "A defendant does not discharge the burden of demonstrating that the underrepresentation was due to systematic exclusion merely by offering statistical evidence of a disparity. A defendant must show, in addition, that the disparity is the result of an improper feature of the jury selection process." (People v. Burgener, supra, 29 Cal.4th at p. 857.)