FILED
                                                                     United States Court of Appeals
                                                                             Tenth Circuit

                      UNITED STATES COURT OF APPEALS                       August 29, 2016

                             FOR THE TENTH CIRCUIT                       Elisabeth A. Shumaker
                                                                             Clerk of Court
                         _________________________________

UNITED STATES OF AMERICA,

      Plaintiff - Appellee,
                                                           No. 15-1268
v.                                               (D.C. No. 1:10-CR-00446-PAB-1)
                                                             (D. Colo.)
CHRISTIAN CASTILLO-ARMENT,

      Defendant - Appellant.
                      _________________________________

                             ORDER AND JUDGMENT*
                         _________________________________

Before HARTZ, O’BRIEN, and PHILLIPS, Circuit Judges.
                   _________________________________

                                       FACTS

      In 2010, Christian Castillo-Arment was indicted for conspiracy to distribute,

and to possess with intent to distribute, five kilograms or more of powder cocaine, in

violation of 21 U.S.C. §§ 846, 841(a)(1) and (b)(1)(A)(ii)(II); and for distribution,

and possession with intent to distribute, five kilograms or more of powder cocaine

and for aiding and abetting that offense, in violation of under 21 U.S.C. § 841(a)(1)

and (b)(1)(A)(ii)(II) and 18 U.S.C. § 2. After a two-day trial in 2011, a jury found

      *
        After examining the briefs and appellate record, this panel has determined
unanimously to honor the parties’ request for a decision on the briefs without oral
argument. See Fed. R. App. P. 34(f); 10th Cir. R. 34.1(G). The case is therefore
submitted without oral argument. This order and judgment is not binding precedent,
except under the doctrines of law of the case, res judicata, and collateral estoppel. It
may be cited, however, for its persuasive value consistent with Fed. R. App. P. 32.1
and 10th Cir. R. 32.1.
Castillo-Arment guilty on both counts. Because Castillo-Arment’s offenses involved

at least five kilograms of powder cocaine, Castillo-Arment’s convictions triggered a

ten-year mandatory minimum sentence under 21 U.S.C. § 841(b)(1)(A)(ii)(II).

      Under the 2010 Sentencing Guidelines, the PSR calculated Castillo-Arment’s

base offense level as 32 (because the conviction was for between five and fifteen

kilograms of cocaine) and his criminal-history category as I. The probation office

recommended a four-level enhancement under U.S.S.G. § 3B1.1(a) because Castillo-

Arment was an organizer or leader in the scheme. Castillo-Arment objected. Thus,

with an adjusted offense level of 36 and a criminal history category of I, the PSR

recommended an advisory guideline range of 188 to 235 months’ imprisonment. On

May 27, 2011, the district court sentenced Castillo-Arment, applying a two-level

enhancement under U.S.S.G. § 3B1.1(c), rather than the four-level enhancement

under U.S.S.G. § 3B1.1(a). This led to a low-end sentence of 151 months’

imprisonment.

      On appeal, this court affirmed Castillo-Arment’s convictions but vacated his

sentence. United States v. Castillo-Arment, 497 F. App’x 813 (10th Cir. 2012). We

determined that the district court had erred in calculating Castillo-Arment’s advisory

guideline range because an undercover law enforcement officer, like the confidential

informant involved in Castillo-Arment’s offense, cannot count as a “participant”

under U.S.S.G. § 3B1.1.

      On January 11, 2013, the district court resentenced Castillo-Arment, this time

without the application of any enhancement under U.S.S.G. § 3B1.1. With Castillo-

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Arment’s base offense level of 32 and criminal history category I, his advisory

guidelines range became 121 to 151 months’ imprisonment. Neither party objected to

the calculation. Castillo-Arment requested a 120-month sentence, a one-month

downward variance from the low end of the advisory guidelines range and the

mandatory minimum sentence for his crimes. The district court denied the motion for

a variance and sentenced Castillo-Arment to 121 months’ imprisonment.

      On November 1, 2014, the United States Sentencing Commission’s

Amendment 782 to the Sentencing Guidelines became effective and modified

U.S.S.G. § 2D1.1(c)’s Drug Quantity Table. Specifically, the amendment reduced the

base offense levels for many federal drug trafficking crimes by two levels. In July

2014, Amendment 788 made Amendment 782 retroactive to sentences already final

before Amendment 782 became effective, allowing defendants imprisoned under

those final sentences to seek relief under 18 U.S.C. § 3582(c)(2).

      The Office of the Public Defender, the Probation Office, and the U.S.

Attorney’s Office in the District of Colorado all agreed that Castillo-Arment was

eligible for a sentence reduction under Amendment 782. Based on Amendment 782,

Castillo-Arment’s total offense level dropped from 32 to 30. His criminal history

category remained category I. His new advisory guidelines range was 97 to 121

months. But because Castillo-Arment’s convictions carried a ten-year mandatory

minimum term, his advisory guideline range became 120 to 121 months. See

U.S.S.G. § 5G1.1(c)(2).



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      On October 15, 2015, Castillo-Arment filed an unopposed § 3582(c)(2) motion

based on Amendment 782 requesting that the court reduce his sentence from 121

months to 120 months, the mandatory minimum. The motion noted that the parties

agreed that no hearing was necessary. On July 16, 2015, the district court granted

Castillo-Arment’s motion in a written order, sentencing him to 120 months’

imprisonment.

      On July 28, 2015, 12 days after the entry of the amended judgment, Castillo-

Arment submitted a pro se notice of appeal. The notice of appeal was docketed on

August 3, 2015, 18 days after the entry of judgment. Castillo-Arment was again

appointed counsel from the Federal Public Defender’s office. On November 2, 2015,

Castillo-Arment sent a letter to this court asking that we permit him to proceed pro se

on appeal, apparently because his attorney advised him that he had no viable claim on

appeal.

      On appeal, Castillo-Arment’s appointed counsel has filed an Anders brief and

moved to withdraw, explaining that she has reviewed the record and relevant case

law and determined the appeal to be wholly frivolous. See Anders v. California, 

, 744 (2007). Castillo-Arment did not file a response. Exercising jurisdiction

under 18 U.S.C. § 1291, we affirm and grant counsel’s motion to withdraw.

                                   DISCUSSION

      Because defense counsel has submitted an Anders brief, our task is to “conduct

a full examination of the record to determine whether defendant’s claims are wholly

frivolous.” United States v. Calderon, 

, 930 (10th Cir. 2005) (citing

                                          4


). “Frivolous means ‘[l]acking a legal basis or legal merit; not

serious; not reasonably purposeful.’” United States v. Lain, 

, 1137

(10th Cir. 2011) (alteration in original) (quoting Frivolous, Black’s Law Dictionary

(8th ed. 2004)). “We review de novo the district court’s interpretation of . . . the

sentencing guidelines.” United States v. Sharkey, 

, 1238 (10th Cir.

2008) (quoting United States v. Smartt, 

, 540 (10th Cir. 1997)).

      At the outset, we address whether Castillo-Arment’s pro se notice of appeal is

timely. Criminal defendants must file a notice of appeal within 14 days of the

judgment or order being appealed. Fed. R. App. P. 4(b)(1)(A). While Rule 4(b) is not

jurisdictional, “the time bar in Rule 4(b) must be enforced when properly invoked by

the government.” United States v. Randall, 

, 1241 (10th Cir. 2011)

(quoting United States v. Mitchell, 

, 744 (10th Cir. 2008)). “We may

raise Rule 4(b)’s time bar sua sponte, but this power ‘is limited and should not be

invoked when judicial resources and administration are not implicated and the delay

has not been inordinate.’” 

518 F.3d at 750). The government

has not moved to enforce Rule 4(b)’s time bar and we see no reason to do so sua

sponte.

      We ordinarily review for an abuse of discretion a district court’s denial of a

motion under § 3582(c)(2). 

. The scope of § 3582,

however, is a legal question that we review de novo. United States v. Graham, 

, 1277 (10th Cir. 2013). Although federal courts generally lack jurisdiction

to modify a term of imprisonment once it has been imposed, they may modify a

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sentence when statutorily authorized. 

. Section 3582(c)(2)

permits a district court to modify a sentence where it has sentenced a defendant

“based on a sentencing range that has subsequently been lowered by the Sentencing

Commission.” 18 U.S.C. § 3582(c)(2). “Unless the basis for resentencing falls within

one of the specific categories authorized by section 3582(c), the district court lack[s]

jurisdiction to consider [a defendant’s] request.” 

.

      The district court here followed the correct resentencing procedures as set out

in Dillon v. United States, 

(2010). First, the district court assessed

whether the defendant is eligible for a reduction by determining the amended

guideline range that would have applied if the amendment had been in effect at the

time of the original sentencing (here, Castillo-Arment’s resentencing). 

Second, the district court considered the 18 U.S.C. § 3553(a) factors and determined

whether the defendant should receive a reduction based on “the particular

circumstances of the case.” 

§ 3582(c)(2) motion, Castillo-Arment asked for a 120-month sentence,

stating that “[t]he re-calculation of the Guidelines and recommended sentence

contained herein reflects agreement between the defendant, the United States

Probation Office, and the Office of the United States Attorney that the defendant is

eligible for relief resulting from Amendment 782 . . . .” R. vol. 1 at 87. Because the

mandatory minimum was still in effect, 120 months’ imprisonment was the lowest

sentence that the district court could give Castillo-Arment as district courts may only

go below a mandatory minimum sentence in limited circumstances. See 18 U.S.C.

                                           6
§ 3553(e) and (f). We have been clear in the past that outside those limited

circumstances, district courts generally “ha[ve] no discretion to depart from a

statutorily mandated minimum sentence under 21 U.S.C. § 841.” United States v.

Cornelius, 

, 1326 (10th Cir. 2012); see United States v. Tubens, 

, at *1 (10th Cir. April 5, 2016) (unpublished) ([I]n a situation where a

defendant’s sentence is cabined by a statutory mandatory minimum term of

imprisonment, a district court lacks jurisdiction to grant the defendant’s § 3582

motion.”).

      In its order, the district court adopted Castillo-Arment’s calculations. The

court also stated that “[t]aking into account the factors set forth in 18 U.S.C.

§ 3553(a) and any guideline or statutory reductions, to the extent applicable, the

previously imposed sentence of 121 months[’] imprisonment is reduced to 120

months . . . .” R. vol. 1 at 94. The district court committed no error.

      Finally, any argument that the sentence was substantively unreasonable is

frivolous. Castillo-Arment received the sentence he asked for, equivalent to the

mandatory minimum. That is certainly not substantively unreasonable.

                                    CONCLUSION

      We affirm the district court and grant counsel’s motion to withdraw.


                                             Entered for the Court


                                             Gregory A. Phillips
                                             Circuit Judge


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