Opinion of the Court
GIERKE, Judge:1. A general court-martial composed of officer and enlisted members convicted appellant, contrary to his pleas, of stealing military explosives and illegally importing explosive materials into the United States without a license (18 USC § 842), in violation of Articles 121 and 134, Uniform Code of Military Justice, 10 USC §§ 921 and 934, respectively. The approved sentence provided for a dishonorable discharge, confinement for 2 years, total forfeitures, and reduction to the lowest enlisted grade.
2. The Court of Military Review2 dismissed the charge of importing explosive materials but affirmed the conviction of larceny and the sentence, after reducing the confinement to 18 months. 37 MJ 632, 636 (1993). That court then reconsidered, permitted appellant to file additional assignments of error, and reaffirmed its earlier decision. 38 MJ 633, 635 (1993).
3. We granted review of the following issues:
I
WHETHER THE MILITARY JUDGE ERRED WHEN HE FAILED TO SUPPRESS THE EVIDENCE FOUND DURING THE ILLEGAL CUSTOMS INSPECTION OF THE PACKAGE MAILED BY APPELLANT BECAUSE THE PACKAGE WAS OPENED IN VIOLATION OF THE REQUIREMENT THAT THERE BE “REASONABLE CAUSE TO SUSPECT” THE PACKAGE CONTAINED MERCHANDISE WHICH WAS IMPORTED CONTRARY TO LAW.
*298II
WHETHER APPELLANT’S SENTENCE MUST BE SET ASIDE TO NEGATE THE EFFECTS OF UNLAWFUL COMMAND INFLUENCE ON APPELLANT’S POST-TRIAL CLEMENCY PROCEEDINGS.
We resolve both issues against appellant.
Issue I: Illegal Customs Inspection
4. While in Saudi Arabia during Operation Desert Shield/Desert Storm, appellant stole 3.74 pounds of C-4, a military explosive, from an Army truck. He mailed it to his mother in Colorado. United States Customs agents inspected and seized the package after it arrived at Dulles International Airport.
5. At a pretrial session under Article 39(a), UCMJ, 10 USC § 839(a), appellant moved to suppress the evidence seized by the customs agents. The military judge denied the motion because “the inspection was a valid Customs inspection at a U.S. border.” Before the court below and this Court, appellant asserts that the explosives should have been suppressed as evidence because they were the fruit of an illegal search.
6. Appellant “concedes that ‘border searches’ are not subject to” the Fourth Amendment requirement for a warrant and that the customs inspection after the package arrived at Dulles International Airport was a border search. Final Brief at 5-6. Appellant relies, however, on 19 USC § 482, which authorizes a customs official “to search any trunk or envelope, wherever found, in which he may have a reasonable cause to suspect there is merchandise which was imported contrary to law.” From this he argues that Congress has imposed a statutory requirement that customs agents have “a reasonable cause to suspect” illegal importation before inspecting incoming mail. Final Brief at 6. The Government argues, on the other hand, that 19 USC § 482 only applies to goods “already introduced into the United States” and that the statute applicable to general border searches is 19 USC § 1582, which contains no such “reasonable cause” requirement. Answer to Final Brief at 4-5.
7. We review a military judge’s ruling on a motion to suppress — like other decisions to admit or exclude evidence — for an abuse of discretion. See, e.g., United States v. Johnston, 41 MJ 13,16 (CMA 1994) (admissibility of scientific evidence); United States v. Gray, 40 MJ 77, 80 (CMA 1994) (admissibility of evidence of a witness’ bias); United States v. Mukes, 18 MJ 358, 359 (CMA 1984) (admissibility of evidence of uncharged misconduct). See generally S. Childress & M. Davis, 2 Federal Standards of Review § 11.02 (2d ed.1992) (ruling on admission of evidence reviewed for abuse of discretion). In reviewing a military judge’s ruling on a motion to suppress, we review factfinding under the clearly-erroneous standard and conclusions of law under the de novo standard. United States v. Cardenas, 9 F.3d 1139, 1147 (5th Cir.1993), cert, denied, - U.S. -, 114 S.Ct. 2150, 128 L.Ed.2d 876 (1994); United States v. Mejia, 953 F.2d 461, 464-65 (9th Cir.1991), cert, denied, 504 U.S. 926, 112 S.Ct. 1983, 118 L.Ed.2d 581 (1992). Thus, on a mixed question of law and fact as in this case, a military judge abuses his discretion if his findings of fact are clearly erroneous or his conclusions of law are incorrect.
8. The operative facts in this case are not disputed. The dispute is limited to whether the military judge correctly applied the law in denying the motion to suppress, which we will review de novo.
9. There is no requirement for “reasonable cause” to conduct a border search. We agree with Judge Howard D. Re’s well-reasoned opinion in United States v. Glosser, 750 F.2d 1197, 1201-04 (3d Cir.1984), cert, denied, 471 U.S. 1018, 105 S.Ct. 2025, 85 L.Ed.2d 306 (1985), holding that the “reasonable cause” requirement of 19 USC § 482 only applies to customs searches other than border searches. See also United States v. Taghizadeh, 41 F.3d 1263, 1265-66 (9th Cir. 1994)(en banc); United States v. Smith, 29 F.3d 270, 274 (7th Cir.1994); United States v. Pringle, 576 F.2d 1114, 1116 (5th Cir.1978).
10. Furthermore, even when searches of incoming mail are conducted under 19 USC § 482, “reasonable cause” exists if the package to be searched is thicker and heavier than a normal first-class letter. United States v. Ramsey, 431 U.S. 606, 614-*29915, 97 S.Ct. 1972, 1978, 52 L.Ed.2d 617 (1977); United States v. Smith, 29 F.3d at 274. Appellant’s package containing 3.74 pounds of explosives would clearly meet this standard.
11. For these reasons, we hold that the military judge did not abuse his discretion by denying the defense motion to suppress.
Unlawful Command Influence
12. After appellant was convicted and sentenced, Specialist (SPC) Martin Slack, a friend of appellant and a member of the same battalion, attempted to gather letters recommending clemency for appellant. In a post-trial affidavit, SPC Slack asserts that, in doing so, he ran into a “continued pattern of resistance.” See 43 MJ at 305. He attributes his lack of success to unlawful command influence. Final Brief at 12. The Government argues that SPC Slack’s affidavit “amounts to no more than a generalized, unsupported claim of command influence,” so it is insufficient to shift the burden to the Government to negate it. Final Brief at 6.
13. SPC Slack states that he requested support from Staff Sergeant (SSG) Uzziel, appellant’s' first-line supervisor; Sergeant First Class (SFC) Penner, appellant’s mess chief; Command Sergeant Major (CSM) Lockwood, appellant’s battalion sergeant major during Operation Desert Storm; CSM Bates, appellant’s battalion sergeant major after Desert Storm; Captain (CPT) Gavien, appellant’s company commander during Desert Storm; CPT Ott, appellant’s company commander after Desert Storm; and Lieutenant Colonel (LTC) Van Horn, appellant’s battalion commander. All except SFC Penner declined.
14. According to SPC Slack, SSG Uzziel promised a “strong letter.” After CSM Bates “instructed him [SSG Uzziel] to review PFC Ayala’s counseling file,” SSG Uzziel informed SPC Slack that he could not “in good conscience” provide a letter of recommendation.
15. SPC Slack states that SFC Penner supported appellant’s request for clemency, and he did so even after being advised by the company first sergeant that “it was not a wise career move.”
16. SPC Slack’s affidavit asserts that CSM Lockwood told him that providing a favorable letter “would not be a problem.” When SPC Slack returned to obtain the letter, he says that CSM Lockwood said that he was unwilling to write a letter of recommendation unless appellant’s current sergeant major (CSM Bates) would also provide a letter.
17. SPC Slack states that CSM Bates was unwilling to provide a letter. According to the affidavit, CSM Bates told SPC Slack that he “was putting [him]self at risk career-wise by pushing things for PFC Ayala.”
18. The affidavit further recites that both CPT Gavien and CPT Ott declined to recommend clemency because “it would be inconsistent with the chain of command.” Finally, SPC Slack states that LTC Van Horn refused to see him, but the battalion legal noncommissioned officer informed him that LTC Van Horn did not desire to “speak out against the chain of command.”
19. The defense has the initial burden of producing sufficient evidence to raise unlawful command influence. See Green v. Widdecke, 19 USCMA 576, 579, 42 CMR 178, 181 (1970) (“[Generalized, unsupported claims of ‘command control’ will not suffice to create a justiciable issue.”). As we said in United States v. Johnston, 39 MJ 242, 244 (1994), “[T]he threshold triggering further inquiry should be low, but it must be more than a bare allegation or mere speculation.” See United States v. Allen, 33 MJ 209, 212 (CMA 1991) (“Proof of [command influence] in the air, so to speak, will not do.”), cert, denied, 503 U.S. 936, 112 S.Ct. 1473, 117 L.Ed.2d 617 (1992).
20. The burden of disproving the existence of unlawful command influence or proving that it did not affect the proceeding does not shift to the Government until the defense meets its burden of production. See United States v. Thomas, 22 MJ 388, 396 (CMA 1986), cert, denied, 479 U.S. 1085, 107 S.Ct. 1289, 94 L.Ed.2d 146 (1987); United States v. Rosser, 6 MJ 267 (CMA 1979). See *300also D. Schlueter, Military Criminal Justice: Practice and Procedure (hereafter Schlueter) § 6-7 at 269 (3d ed.1992). The issue is not “raised” until the defense meets its burden of production. The quantum of evidence necessary to raise unlawful command influence is the same as that required to submit a factual issue to the trier of fact. See United States v. Cruz, 20 MJ 873, 886 (ACMR 1985), rev’d on other grounds, 25 MJ 326 (CMA 1987); Schlueter, supra. Cf. United States v. McMonagle, 38 MJ 53, 58 (CMA 1993), quoting United States v. Simmelkjaer, 18 USCMA 406, 410, 40 CMR 118, 122 (1969) (affirmative defense is “reasonably raised” if “record contains some evidence to which the [trier of fact] may attach credit if it so desires”).
21. What is missing from SPC Slack’s affidavit (¶ 12) is evidence that anyone acting with the “mantle of command authority” unlawfully coerced or influenced any of the officers or noncommissioned officers approached by SPC Slack. See Art. 37(a), UCMJ, 10 USC § 837(a); United States v. Stombaugh, 40 MJ 208, 211 (CMA 1994). SPC Slack’s affidavit does not indicate whether the first sergeant’s advice to SFC Penner that support for appellant “was not a wise career move” was intended to coerce SFC Penner or was intended as well-meaning advice against blindly supporting a marginal soldier who had been convicted of serious offenses. It also does not indicate how SFC Penner interpreted the admonition. Assuming, arguendo, that the efforts of the unnamed first sergeant to influence SFC Penner constitute unlawful command influence, appellant would not be entitled to relief, because the attempt failed. SFC Penner provided the requested letter. See United States v. Allen, 33 MJ at 212-13.
22. SFC Penner’s letter also provides some insight into CSM Bates’ admonition to SSG Uzziel to “review PFC Ayala’s counseling file.” SFC Penner wrote, “While I can not honestly say Pfc Ayala was a trouble free soldier or an outstanding cook: I can say in all honesty that he was one of the most tactically proficient soldiers in my command.” (Emphasis added.) The letter also provides some insight into SSG Uzziel’s statement that he could not “in good conscience” recommend clemency after reviewing appellant’s file. Cf. United States v. Wallace, 39 MJ 284 (CMA 1994) (no unlawful command influence where superior commander suggested that subordinate reconsider recommendation in light of additional information).
23. SPC Slack’s affidavit does not assert that CSM Bates attempted to influence CSM Lockwood. Even if he did, however, any influence exercised by CSM Bates on CSM Lockwood would not constitute unlawful command influence, unless the evidence showed that CSM Bates was acting with the “mantle of command authority.” See United States v. Stombaugh, 40 MJ at 212 (pressure from peers is not unlawful command influence, but may constitute “interference with access to witnesses”). In short, Slack’s affidavit contains no evidence of unlawful influence on CSM Lockwood, “command” or otherwise.
24. The evidence indicates that the remaining officers and noncommissioned officers merely were unwilling to rally to appellant’s support after he had been properly convicted and sentenced. CPT Ott, CSM Bates, SFC Penner, and SSG Uzziel all were members of LTC Van Horn’s battalion. There is no evidence that they were coerced or intimidated by anyone. CPT Ott was the accuser in the case. He had preferred the charges and forwarded them with a recommendation for a general court-martial. LTC Van Horn, CPT Ott’s superior, unsuccessfully tried to support appellant, recommending disposition of the charges by a special court-martial empowered to adjudge a bad-conduct discharge. In his forwarding endorsement, LTC Van Horn said, “[W]e have a case of an immature, but otherwise good soldier making a mistake.” The general court-martial convening authority rejected LTC Van Horn’s recommendation (and that of the Article 32, UCMJ, 10 USC § 832, investigating officer as well) and referred the case to a general court-martial. Because he had already expressed his support for appellant, LTC Van Horn’s refusal to submit additional clemency matters is understandable and suggests nothing sinister.
*30125. Even if CSM Bates’ admonition to SSG Uzziel to read appellant’s file before recommending clemency was coercive, there is no evidence that CSM Bates’ actions unlawfully deterred SSG Uzziel from recommending clemency. SSG Uzziel’s explanation only invokes his own conscience, not fear of CSM Bates or anyone in the chain of command.
26. CSM Bates’ alleged admonition to SPC Slack that he was risking his career by supporting appellant is like the first sergeant’s admonition to SFC Penner: we cannot tell whether it was intended to coerce or to be helpful. In any event, we need not decide how it was intended or how it was received, because SPC Slack was not deterred from his efforts.
27. CPT Gavlen’s unwillingness to take a position “inconsistent with the chain of command” is not further explained, but there is not a scintilla of evidence that his reluctance was due to command coercion or influence.
28. Based on our review of the record, we agree with the court below that SPC Slack’s affidavit is insufficient to raise the issue of unlawful command influence.
Decision
The decision of the United States Army Court of Military Review on further review is affirmed.
Judges COX and CRAWFORD concur.. See 41 MJ 213, 229 n. * (1994).