In U.S. v. Drayton, the issue before Magistrate Judge Sargent was this:
"The defendant, who is black or African American, argues that, cognizant of a great disparity in the racial demographics of the Abingdon and Roanoke Divisions, the government intentionally brought this matter in the Abingdon Division in an effort to exclude blacks or African Americans from the jury pool and, thus, from the jury itself."
The motion was denied, since the defendant could not show intent to discriminate.
Once in my life I have exercised a peremptory strike against a black member of the jury pool, after he had tried every way in the world to get out of the case during voir dire, stating in fairly stark terms that he was biased in favor of the other side. The judge would not strike him for cause, but opposing counsel laughed later, "I think your strikes are safe from constitutional challenge."