Dismissed by unpublished PER CURIAM opinion.
Unpublished opinions are not binding precedent in this circuit.
PER CURIAM:
Keenan Kester Cofield, while in federal custody, sought to appeal the district court’s order denying relief on his 28 U.S.C.A. § 2241 (West 2006 & Supp.2012) petition in which he challenged his Maryland state sentence and detainer. The order is not appealable unless a circuit justice or judge issues a certificate of ap-pealability. 28 U.S.C. § 2253(c)(1)(A) (2006). A certificate of appealability will not issue absent “a substantial showing of the denial of a constitutional right.” 28 U.S.C. § 2253(c)(2) (2006). When the district court denies relief on the merits, a prisoner satisfies this standard by demonstrating that reasonable jurists would find that the district court’s assessment of the constitutional claims is debatable or wrong. Slack v. McDaniel, 529 U.S. 473, 484, 120 S.Ct. 1595, 146 L.Ed.2d 542 (2000); see Miller-El v. Cockrell, 537 U.S. 322, 336-38, 123 S.Ct. 1029, 154 L.Ed.2d 931 (2003). When the district court denies relief on procedural grounds, the prisoner must demonstrate both that the dispositive procedural ruling is debatable, and that the petition states a debatable claim of the denial of a constitutional right. Slack, 529 U.S. at 484-85, 120 S.Ct. 1595.
We have independently reviewed the record and conclude that Cofield has not made the requisite showing. Accordingly, we deny a certificate of appealability and dismiss the appeal. We dispense with oral argument because the facts and legal contentions are adequately presented in the materials before this court and argument would not aid the decisional process.
DISMISSED.