United States Court of Appeals
                              For the Eighth Circuit
                          ___________________________

                                  No. 15-2213
                          ___________________________

                              United States of America

                         lllllllllllllllllllll Plaintiff - Appellee

                                            v.

                                    Karina Carrasco

                        lllllllllllllllllllll Defendant - Appellant
                                        ____________

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

                            Submitted: February 11, 2016
                               Filed: March 4, 2016
                                  [Unpublished]
                                  ____________

Before LOKEN, ARNOLD, and BENTON, Circuit Judges.
                           ____________

PER CURIAM.

      Karina Carrasco appeals the district court's1 revocation of her supervised release
and her resulting sentence. We affirm.


      1
      The Honorable Greg Kays, Chief Judge, United States District Court for the
Western District of Missouri.
       Carrasco pleaded guilty to importing marijuana, see 21 U.S.C. §§ 952(a) and
960(b)(4), and began serving a term of supervised release following her imprisonment.
Carrasco's supervised release was conditioned on her refraining from unlawfully using
controlled substances, and Carrasco was required to wear sweat patches that could
detect her use of them. After several of her patches tested negative for controlled
substances, no fewer than nine subsequent patches tested positive for
methamphetamine.

        Carrasco, who denied any drug use, then paid to have hair and nail samples
collected and tested. The record shows that a hair test could detect illegal substances
between 14 and 90 days after their use, but we have found nothing in the record that
reveals the corresponding detection range for a nail test. Both samples tested negative
for illegal substances, including methamphetamine. But five more sweat patches tested
positive for methamphetamine in the following months, and the district court revoked
Carrasco's supervised release based on the methamphetamine-positive tests.

       The district court may revoke supervised release "if the government proves by
a preponderance of the evidence that the defendant violated a condition of supervised
release." United States v. Boyd, 

, 919 (8th Cir. 2015). We review the
district court's findings of fact for clear error. 

that the district court clearly erred by giving more weight
to the fourteen methamphetamine-positive sweat patches than to the
methamphetamine-negative hair and nail samples. She argues, essentially, that since
the evidence is in equipoise, the district court erred in finding that it preponderated in
the government's favor. But the evidence is not in equipoise: We have explained that
sweat patches are generally reliable in detecting drug use and that hair tests are not,
United States v. Meyer, 

, 869–70 (8th Cir. 2007), and evidence of the
general accuracy and reliability of hair and nail tests is wholly absent from the present
record. Although "[t]here may well be certain instances where offenders offer

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compelling reasons to believe that positive test results from sweat patches are
erroneous," 

Carrasco offers no convincing explanation for these positive
results. She provides nothing beyond her unsupported denials of drug use and the
results of her hair and nail tests. We also note that the hair and nail samples were not
taken on the same days as any of the patch tests, so there is no necessary conflict
between the tests so far as the record goes. And Carrasco does not argue that there is.

        Even if we assumed that the hair and nail tests cast some doubt on the validity
of the positive sweat-patch tests that preceded them, those tests could have little if any
similar effect on the results of sweat patches tested later or outside the hair and nail
tests' detection ranges. "One time, at least in the context of probation, is one time too
many." 

We therefore cannot say that "we have a definite and firm
conviction that the District Court was mistaken" in finding that the government proved
by a preponderance of the evidence that Carrasco violated a condition of her
supervised release. See 

.

      Carrasco also maintains that the district court's sentence of twelve months'
imprisonment followed by five additional years of supervised release is substantively
unreasonable. Carrasco's Guidelines sentencing range was three to nine months'
imprisonment and up to life of supervised release, and she faced a statutory maximum
sentence of 24 months' imprisonment.

       We review the substantive reasonableness of a revocation sentence for an abuse
of discretion. United States v. Goodon, 

, 376 (8th Cir. 2014). Carrasco
does not explain how the district court abused its discretion: She contends only that
the punishment is excessive and unreasonable. But the sentence is well within
statutory limits, and the district court reviewed and applied the 18 U.S.C. § 3553(a)
sentencing factors, giving particular attention to protecting the public and Carrasco's
refusal to acknowledge her drug problem. The sentence is therefore well within the



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district court's discretion. See United States v. Larison, 

, 922–24 (8th Cir.
2006).

      Affirmed.
                        ______________________________




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