Is a criminal defendant's right to counsel of choice restricted?

A criminal defendant's sixth amendment right to counsel of choice is circumscribed in several important respects. For instance, a defendant may not "insist on the counsel of an attorney who has a previous or on-going relationship with an opposing party, even when the opposing party is the Government." Wheat v. United States, 486 U.S. 153, 159, 108 S.Ct. 1692, 1697, 100 L.Ed.2d 140 (1988). Nor can a defendant insist upon being represented by an attorney "where the attorney in question is potentially in a position to use privileged information obtained during prior representation of the movant." United States v. James, 708 F.2d 40, 45 (2d Cir.1983) (quotation marks and citations omitted).