United States Court of Appeals
                              For the Eighth Circuit
                          ___________________________

                                  No. 15-1966
                          ___________________________

                               United States of America

                         lllllllllllllllllllll Plaintiff - Appellee

                                            v.

                               Robert Fount Mahan, Jr.

                        lllllllllllllllllllll Defendant - Appellant
                                        ____________

                      Appeal from United States District Court
                for the Western District of Missouri - Jefferson City
                                  ____________

                             Submitted: February 2, 2016
                               Filed: February 5, 2016
                                    [Unpublished]
                                   ____________

Before WOLLMAN, ARNOLD, and SMITH, Circuit Judges.
                         ____________

PER CURIAM.

       Robert Mahan, Jr. directly appeals after he pleaded guilty, pursuant to a written
plea agreement, to a felon-in-possession offense, and the district court1sentenced him

      1
        The Honorable Beth Phillips, United States District Judge for the Western
District of Missouri.
to 120 months in prison and three years of supervised release. Mahan’s counsel has
moved to withdraw, and has filed a brief under Anders v. California, 

(1967); and Mahan has filed a pro se supplemental brief. For the reasons that follow,
we affirm the judgment, and we grant counsel’s motion to withdraw.

        Counsel argues in the Anders brief that Mahan’s plea was not voluntary, but
the issue is not properly before us. See United States v. Umanzor, 

,
1060-61 (8th Cir. 2010) (where defendant did not move to withdraw guilty plea in
district court, he could not challenge voluntariness of plea for first time on direct
appeal, and any claim that plea was involuntary needed to be addressed in 28 U.S.C.
§ 2255 proceedings where factual record could be further developed). Counsel also
argues that the felon-in-possession statute underlying Mahan’s conviction is invalid
under the Missouri Constitution because it violates the right to bear arms, and
accordingly, the conviction and sentence are invalid. These arguments are patently
meritless and do not warrant extended discussion. See United States v. Joos, 

, 586 (8th Cir. 2011); Heart of Am. Grain Inspection Serv., Inc. v. Mo. Dep’t
of Agric., 

, 1103 (8th Cir. 1997) (discussing Supremacy Clause). The
final Anders brief argument addresses pretrial-detention credit, but this matter must
first be raised with the Bureau of Prisons. See United States v. Iversen, 

,
1344 (8th Cir. 1996).

       In his pro se brief, Mahan complains generally of the ambiguity of his plea
agreement, but does not explain what terms are ambiguous or what relief he seeks.
He also raises ineffective-assistance claims, which we decline to consider in this
direct appeal, see United States v. Looking Cloud, 

, 788-89 (8th Cir.
2005); we reject his assertions that alleged misstatements in his plea agreement
undermined the district court’s jurisdiction; and his reliance on Alleyne v. United
States, 

, 2155 (2013), is misplaced. Finally, having reviewed the
record independently as required under Penson v. Ohio, 

(1988), we find



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no nonfrivolous issues for appeal. Accordingly, we affirm, and we grant counsel’s
motion to withdraw.

                          _______________________




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