The Federal Public Defender appointed to represent Eric Dwain Shackleford on appeal from the revocation of his supervised release has moved for leave to withdraw and has filed a brief as required by Anders v. California, 386 U.S. 738, 87 S.Ct. 1396, 18 L.Ed.2d 493 (1967). Shackleford has filed a brief in response challenging the revocation decision, the effectiveness of his trial counsel, and the validity of his sentence in light of United States v. Booker, 543 U.S. 220, 125 S.Ct. 738, 160 L.Ed.2d 621 (2005). Shackleford also has filed a motion for the appointment of substitute counsel or, in the alternative, to proceed pro se.

Our review of the brief filed by counsel, Shackleford’s response, and the record discloses no nonfrivolous issue for appeal. We decline to address any claim of ineffecfive assistance of counsel, without prejudice to Shackleford’s right to assert such claims in a motion pursuant to 28 U.S.C. § 2255. United States v. Higdon, 832 F.2d 312, 313-14 (5th Cir. 1987). Shackle-ford’s motion for the appointment of substitute counsel, or in the alternative to proceed pro se, is DENIED. See United States v. Wagner, 158 F.3d 901, 902-03 (5th Cir. 1998). Counsel’s motion for leave to withdraw is GRANTED, counsel is excused from further responsibilities, and the appeal is DISMISSED. See 5th Cir. R. 42.2.