                  United States Court of Appeals
                             For the Eighth Circuit
                         ___________________________

                                 No. 13-3365
                         ___________________________

                              United States of America

                         lllllllllllllllllllll Plaintiff - Appellee

                                            v.

                                     Marshall Polk

                       lllllllllllllllllllll Defendant - Appellant
                                       ____________

                     Appeal from United States District Court
                    for the Northern District of Iowa, Waterloo
                                  ____________

                              Submitted: April 16, 2014
                                Filed: April 21, 2014
                                    [Unpublished]
                                   ____________

Before BYE, GRUENDER, and SHEPHERD, Circuit Judges.
                           ____________

PER CURIAM.

      Marshall Polk directly appeals after he pled guilty to a drug-conspiracy charge,
and the district court1 sentenced him within the calculated Guidelines range. His

      1
      The Honorable Linda R. Reade, Chief Judge, United States District Court for
the Northern District of Iowa.
counsel has moved to withdraw, and has filed a brief under Anders v. California, 386
U.S. 738 (1967), arguing that the district court calculated the Guidelines range based
on clearly erroneous findings with respect to the relevant drug quantity and Polk’s
role in the offense, and that the court imposed an unreasonable sentence. Polk has
filed a pro se supplemental brief, arguing that the district court should have held a
competency hearing before accepting his guilty plea.

       Upon careful review, we conclude that the district court did not clearly err in
making the factual findings challenged by counsel, as they were based primarily on
the testimony of a co-conspirator whom the court credited. See United States v.
Walker, 688 F.3d 416, 421-22 (8th Cir. 2012) (sentencing court may determine drug
quantity based on testimony of co-conspirator alone; witness credibility is issue for
sentencing judge and virtually unreviewable on appeal); see also United States v.
Payton, 636 F.3d 1027, 1046 (8th Cir. 2011) (district court’s drug-quantity
calculation is reviewed for clear error); United States v. Mesner, 377 F.3d 849, 851
(8th Cir. 2004) (district court’s decision to assess sentencing enhancement based
upon defendant’s role in offense is reviewed for clear error). We also conclude that
Polk’s sentence is not unreasonable. See United States v. Feemster, 572 F.3d 455,
461 (8th Cir. 2009) (en banc) (review of sentence includes considering substantive
reasonableness of sentence under totality of circumstances; where sentence falls
within Guidelines range, appeals court may, but is not required to, apply presumption
of reasonableness). In addition, we conclude that there is no merit to Polk’s pro se
argument, because his counsel did not request a competency hearing and the record
does not indicate that a competency hearing was warranted. See 18 U.S.C. § 4241(a)
(court shall order competency hearing upon its own motion if there is reasonable
cause to believe defendant is not competent).

      Finally, having independently reviewed the record under Penson v. Ohio, 488
U.S. 75 (1988), we find no nonfrivolous issues. Accordingly, we affirm the
judgment.

                                         -2-
      As for counsel’s motion to withdraw, we conclude that allowing counsel to
withdraw at this time would not be consistent with the Eighth Circuit’s 1994
Amendment to Part V of the Plan to Implement The Criminal Justice Act of 1964.
We therefore deny counsel’s motion to withdraw as premature, without prejudice to
counsel refiling the motion upon fulfilling the duties set forth in the Amendment.
                       ______________________________




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