[PUBLISH]

IN THE UNITED STATES COURT OF APPEALS

FOR THE ELEVENTH CIRCUIT

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No. 19-13542

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D.C. Docket No. 8:19-cr-00005-WFJ-AAS-1

UNITED STATES OF AMERICA, 

 Plaintiff-Appellee,

versus

MARIO ALBERTO MONTENEGRO, 

 Defendant-Appellant.

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Appeal from the United States District Court

for the Middle District of Florida

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(June 11, 2021)

Before BRANCH, GRANT, and TJOFLAT, Circuit Judges.

BRANCH, Circuit Judge: 

Mario Alberto Montenegro appeals the district court’s application of a 

firearms enhancement over both parties’ objections, pursuant to U.S.S.G. 

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§ 2D1.1(b)(1),1 to his total 62-month sentence for (1) conspiracy to distribute and 

to possess with intent to distribute 500 grams or more of cocaine, in violation of 21 

U.S.C. §§ 846, 841(a)(1) and (b)(1)(B)(ii), and (2) possession with intent to 

distribute 500 grams or more of cocaine, in violation of 21 U.S.C. § 841(a)(1) and 

(b)(1)(B)(ii). He argues that in objecting to the firearms enhancement, the 

government ceded that it did not meet its burden of proving that the firearm was 

used in connection with his offenses. After careful consideration, we affirm the 

district court.

I. Background

Mario Alberto Montenegro was indicted by a grand jury and subsequently 

pleaded guilty to one count of conspiracy to distribute and to possess with intent to 

distribute 500 grams or more of cocaine and one count of possession with intent to 

distribute 500 grams or more of cocaine.

According to the presentence investigation report (“PSI”), Montenegro sold 

58 grams of cocaine to an undercover officer on November 13, 2018. The sale 

took place at Montenegro’s residence, a small trailer. On December 12, 2018, 

Montenegro sold another 1,994 grams of cocaine to the undercover officer after 

they met outside a store. The undercover officer arrested Montenegro after the 

1 U.S.S.G. § 2D1.1(b)(1) provides that “[i]f a dangerous weapon (including a firearm) 

was possessed, increase [the base offense level] by 2 levels.”

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sale. Following Montenegro’s arrest, Drug Enforcement Administration (“DEA”) 

agents obtained a warrant, searched his residence, and found a .22-caliber bolt 

action rifle on the trailer dashboard, close to the bed; a drug ledger on the kitchen 

table, which was also near the bed; a box of .22-caliber bullets in a cabinet; and 

another 811 grams of cocaine. On January 3, 2019, a grand jury indicted 

Montenegro for possession with intent to distribute 500 grams or more of cocaine 

and conspiracy to possess with intent to distribute 500 grams or more of cocaine.

Using the 2018 United States Sentencing Guidelines, the probation office 

prepared the PSI and calculated Montenegro’s base offense level as 26, pursuant to 

U.S.S.G. § 2D1.1(a)(5).2

 The probation office applied a two-level enhancement 

for possession of a dangerous weapon, pursuant to U.S.S.G. § 2D1.1(b)(1), due to 

“the loaded 22-caliber bolt action rifle that was possessed in [Montenegro’s] 

residence with 811 grams of cocaine and a drug ledger.”3

 Montenegro also 

2

 The drug quantity conversion table included in U.S.S.G. § 2D1.1 provides that when, 

as here, the offense involved at least 2 kilograms but less than 3.5 kilograms of cocaine, the base 

offense level is 26. Montenegro’s offense involved 2.863 kilograms of cocaine.

3 Based on the application of the firearms enhancement, the probation office determined 

that Montenegro did not qualify for an additional two-level reduction under the safety-valve 

provision of U.S.S.G. § 2D1.1(b)(18). The district court did not explicitly rule on the application 

of the safety valve, but it implicitly adopted the PSI by sentencing Montenegro within the 

recommended guidelines range and not applying a safety-valve reduction. At sentencing, 

Montenegro objected to the district court’s implicit denial of the safety-valve. As we explained 

in United States v. Carillo-Ayala, the application of a § 2D1.1(b)(1) enhancement does not

necessarily mean that safety-valve relief is unavailable. 713 F.3d 82, 91 (11th Cir. 2013).

On appeal, Montenegro asks that if we remand for resentencing, we direct the district 

court to consider the application of the safety valve. Although Montenegro did properly preserve 

the issue below, he only raises the potential safety-valve error in one sentence in his initial brief. 

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received a three-level reduction for acceptance of responsibility under U.S.S.G. 

§ 3E1.1. Thus, the PSI showed his total adjusted offense level was 25. Together 

with his criminal history category of I, Montenegro’s advisory guidelines range 

was 60–71 months’ imprisonment.

4

Prior to sentencing, Montenegro and the government both objected to the 

application of the firearms enhancement in the PSI, arguing that there was not an 

established nexus between the rifle’s presence in Montenegro’s trailer and the 

crime. The probation office responded to and disagreed with the parties’ 

objections in the addendum to the PSI, explaining as follows:

The probation office maintains that the enhancement at USSG §2D1.1(b)(1) 

is applicable in this case. According to USSG §2D1.1(b)(1), if a dangerous 

weapon (including a firearm) was possessed, increase by two levels.

Further, according to USSG §2D1.1, Application Note 11(A), the 

enhancement should be applied if the weapon was present, unless it is 

clearly improbable that the weapon was connected with the offense. In this 

Consequently, Montenegro has waived this argument on appeal because he failed to “plainly and 

prominently” raise it by “devoting a discrete section of his argument” to the claim. Sapuppo v. 

Allstate Floridian Ins. Co., 739 F.3d 678, 681 (11th Cir. 2014) (quoting Cole v. U.S. Att’y Gen., 

712 F.3d 517, 530 (11th Cir. 2013), abrogated on other grounds by Nasrallah v. Barr, 140 S. Ct. 

1683 (2020)). As we have explained, “simply stating that an issue exists, without further 

argument or discussion,” as Montenegro has done, “constitutes abandonment of that issue and 

precludes our considering the issue on appeal.” Singh v. U.S. Att’y Gen., 561 F.3d 1275, 1278 

(11th Cir. 2009). Montenegro does address the safety valve in slightly more detail in his reply 

brief, but we do not consider arguments presented for the first time in an appellant’s reply brief. 

See Big Top Koolers, Inc. v. Circus-Man Snacks, Inc., 528 F.3d 839, 844 (11th Cir. 2008); 

United States v. Coy, 19 F.3d 629, 632 n.7 (11th Cir. 1994). Additionally, we note that the relief 

Montenegro asks for—that on remand for resentencing, the district court rule on the safety valve 

in the first instance—is unavailable because we affirm the district court’s sentence.

4

 The advisory guidelines range was 57 to 71 months’ imprisonment, but because 

Montenegro’s offenses carried a statutory minimum term of 60 months’ imprisonment, the 

bottom of the guidelines range was increased from 57 to 60 months’ imprisonment.

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case, at the time of the execution of the search warrant, agents located a 22-

caliber bolt action rifle bearing serial number 11530414, on the dash of the 

trailer, next to the bed. The rifle had one round loaded in the chamber and 

round in the magazine. A drug ledger was located on the kitchen table next 

to the bed of the trailer, a box of 22 caliber bullets in a cabinet, and 811 

grams of cocaine. The defendant was residing in this travel trailer and he 

sold 58 grams of cocaine to an undercover officer from this residence on 

November 13, 2018. Therefore, the probation office contends that it is not 

clearly improbable that the weapon was connected with the offense, and the

two-level enhancement at USSG §2D1.1(b)(1) is applicable.

At sentencing, the district court overruled the parties’ objections to the 

firearm enhancement, finding that there was a sufficient nexus between the rifle 

and Montenegro’s drug sales because (1) the first sale to the undercover officer 

took place at Montenegro’s “very small trailer” where the rifle was located; 

(2) Montenegro was using the trailer as his “stash house” where he kept cocaine

and people knew he sold drugs out of his trailer; and (3) there was a drug sales 

ledger in “very close proximity” to the gun. Accordingly, the district court adopted 

the PSI, finding that the applicable guidelines range was 60 to 71 months’ 

imprisonment.

Montenegro requested a sentence of five years’ imprisonment, and the 

government stated that it was “seeking a guideline sentence.”5

 The district court 

explained that after considering the advisory guidelines and the 18 U.S.C. 

§ 3553(a) factors, a sentence consisting of concurrent terms of 62 months’ 

5 Montenegro noted that, if the district court had not applied the firearms enhancement 

and had awarded him safety-valve relief, it would have “put him at three years” imprisonment.

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imprisonment was appropriate. Montenegro again objected to the application of 

the firearms enhancement. This appeal followed.

II. Standard of Review

“We review the district court’s findings of fact under U.S.S.G. § 2D1.1(b)(1) 

for clear error, and the application of the Sentencing Guidelines to those facts de 

novo.” United States v. Pham, 463 F.3d 1239, 1245 (11th Cir. 2006) (quotation 

omitted). “For a factual finding to be clearly erroneous, we must be left with a 

definite and firm conviction that the court made a mistake.” United States v. Tejas, 

868 F.3d 1242, 1244 (11th Cir. 2017).

III. Discussion

The main focus of Montenegro’s appeal is that the government, in objecting

to the firearms enhancement, admitted that it had no evidence Montenegro “used 

this old bolt action rifle for any purpose that would relate to the underlying 

offense.” Accordingly, Montenegro argues that the district court clearly erred in 

applying the firearms enhancement to him because it relied on speculation to 

conclude that there was a nexus between the rifle and his drug sales. Specifically, 

he asserts that the facts on which the district court relied—that Montenegro’s first

drug sale occurred at the trailer; that he used the trailer as a “stash house,” and that 

people knew Montenegro sold drugs out of his home; and that the rifle was in close 

proximity to the drug ledger—do not by themselves create a nexus. Throughout, 

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he analogizes the facts of his case to United States v. Stallings, 463 F.3d 1218 

(11th Cir. 2006), and urges us to reach the same conclusion—that the government 

failed to meet its burden in justifying the enhancement. We disagree.

A drug-trafficking offender is subject to a two-level sentencing enhancement 

“[i]f a dangerous weapon (including a firearm) was possessed.” U.S.S.G. 

§ 2D1.1(b)(1). The U.S.S.G. commentary further explains that “[t]he enhancement 

for weapon possession . . . reflects the increased danger of violence when drug 

traffickers possess weapons. The enhancement should be applied if the weapon 

was present, unless it is clearly improbable that the weapon was connected with the 

offense.” Id. at cmt. n.11(A).

To justify a firearms enhancement, the government must establish by a 

preponderance of the evidence either (1) that a “firearm was present at the site of 

the charged conduct,” or (2) “that the defendant possessed a firearm during 

conduct associated with the offense of conviction.” Stallings, 463 F.3d. at 1220. 

The government must show “some nexus beyond mere possession between the 

firearms and the drug crime.” Id. at 1221. However, the government is not 

required to prove that the firearm was used to facilitate the distribution of drugs for 

the firearms enhancement to apply; its mere presence during the drug offense is 

sufficient. United States v. Audain, 254 F.3d 1286, 1289 (11th Cir. 2001). 

Evidence of “proximity between guns and drugs, without more, is sufficient to 

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meet the government’s initial burden under § 2D1.1(b)(1).” United States v. 

Carillo-Ayala, 713 F.3d 82, 91–92 (11th Cir. 2013). We have also explained that:

other facts, such as whether the firearm is loaded, or inside a locked 

container, might be relevant to negate a connection, [but] there is a 

strong presumption that a defendant aware of the weapon’s presence 

will think of using it if his illegal activities are threatened. The 

firearm’s potential use is critical.

Id. at 92. 

If the government meets its initial burden, the burden then shifts to the 

defendant to show “that a connection between the weapon and the offense was 

clearly improbable.” Stallings, 463 F.3d at 1220 (quotation omitted). As we 

explained in Carillo-Ayala, “the § 2D1.1(b)(1) enhancement . . . places a heavy 

burden of negation on the defendant.” 713 F.3d at 90.

Here, the government has met its burden by producing evidence that the rifle 

was present at the site of the drug possession charge. The undisputed facts in the 

PSI show that Montenegro sold more than two kilograms of cocaine to an 

undercover officer; that the first sale occurred in Montenegro’s trailer home; and 

that during the search of his trailer home, officers found more cocaine, a drug 

ledger, and a loaded rifle. See United States v. Trujillo, 146 F.3d 838, 847 (11th 

Cir. 1998) (affirming application of firearms enhancement where a firearm was 

found in an office of a warehouse and drug transactions took place “nearby in and 

around the warehouse”); United States v. Hall, 46 F.3d 62, 64 (11th Cir. 1995) 

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(affirming application of enhancement when firearm was possessed during the 

drug offense, as shown by the proximity of the handgun to several drug-related 

objects located in the house where conversations concerning drug-trafficking 

activity occurred).

With the government having established a nexus between Montenegro’s 

drug offenses and the rifle, the burden then shifted back to Montenegro to negate 

any possible connection. At sentencing, Montenegro argued that the enhancement 

should not apply because there was no evidence that the rifle had been present in 

his trailer home during the November 13, 2018 sale and that the rifle was in his 

trailer for hunting purposes only. In so arguing, he failed to meet his burden to 

negate the nexus presented by the government.

First, presenting another reason for why the rifle may have been present in 

Montenegro’s trailer home does not establish that it was clearly improbable that 

the rifle was also possessed in connection with his drug offenses. The gun may 

have been used for hunting, but a gun, after all, has many different uses and one 

use does not exclude the others. See, e.g., United States v. Delgado, 981 F.3d 889, 

903 (11th Cir. 2020) (noting with approval the district court’s observation that 

“firearms can have more than one purpose,” including availability to protect the 

defendant or his stash of drugs).

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Second, Montenegro’s argument that there is no evidence that he had the 

gun with him during the drug transactions fails because it ignores a key fact: 

Montenegro was indicted for possession of cocaine with intent to distribute, not for 

distributing cocaine. The rifle was located in his trailer home along with cocaine 

and a drug sales ledger. Thus, the rifle was present at the site of the charged 

conduct, even if the rifle was not present at either drug sale. See, e.g., id. at 902–

03 (finding that application of enhancement was proper when defendant was 

charged with importation of controlled substances and several firearms were found 

at his home—the intended destination for the shipments of illegal substances—in 

the same place as digital scales and another illegal substance).

Accordingly, Montenegro does not satisfy the “heavy burden of negation” 

placed on him to overcome the application of the firearms enhancement. CarilloAyala, 713 F.3d at 90. In light of the record, the district court’s factual findings 

related to the firearms enhancement were not clearly erroneous, and the district 

court did not err in applying the enhancement.

Montenegro nonetheless argues that the government failed to meet its 

burden because, prior to sentencing, it agreed with him that the firearms 

enhancement should not be applied. As an initial matter, the district court—not the 

government—applies the guidelines and determines the appropriate sentence. See 

United States v. Boyd, 975 F.3d 1185, 1190–91 (11th Cir. 2020) (“It is wellUSCA11 Case: 19-13542 Date Filed: 06/11/2021 Page: 10 of 12
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established that only the district court determines the guideline range.” (citing 

Molina-Martinez v. United States, 136 S. Ct. 1338, 1342 (2016), and U.S.S.G. 

§ 1B1.1(a)). Accordingly, the district court may reach a different conclusion from 

the parties when it applies the guidelines. And while Montenegro takes issue with 

the fact that the government has now reversed course and is arguing for the 

application of the firearms enhancement, he cites to no caselaw holding that the 

government is bound by a position that it took prior to sentencing.

Montenegro also relies on Stallings to challenge whether the government 

met its burden of proof for the application of the firearms enhancement. In 

Stallings, the district court applied a firearms enhancement after the police found 

three firearms in one of the defendants’ homes. 463 F.3d at 1220. We vacated the 

firearms enhancement because there was no evidence that any activities related to 

the drug conspiracy occurred at the home in question, there was no evidence that 

the defendant possessed the firearms in relation to any of his drug-trafficking 

activities, and the government failed to address the possibility that the firearms 

could have belonged to another adult in the residence. Id. at 1220–21. 

The facts of Montenegro’s case are different from those in Stallings in three 

notable ways. First, the ownership of the rifle is not in dispute like the ownership 

of the firearms was in Stallings. Montenegro was the only resident of the trailer,

and he does not dispute that the rifle belongs to him. Second, the rifle was located 

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at a drug transaction site. Montenegro’s first drug sale to the undercover officer 

took place at his trailer, where the rifle was later found. Third, objects related to 

Montenegro’s drug sales—cocaine and a sale ledger—were found in close 

proximity to the rifle, thus suggesting they are linked. Thus, given the salient 

differences between Montenegro’s case and Stallings, his reliance on Stallings is 

misplaced.

For these reasons, we affirm.

AFFIRMED.

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