KRAVITCH, Circuit Judge:
In 1984, Congress amended 31 U.S.C. § 5317 to add a provision to expand the authority of Customs officers to search persons and property entering and departing the United States for currency reporting violations. In this issue of first impression,1 the constitutionality of the 1984 amendment to 31 U.S.C. § 5317(b)2 is challenged.
Appellant Edgar Hernandez-Salazar and two codefendants were indicted for currency reporting offenses in connection with appellant’s attempt to transport in excess of $200,000 in United States currency in a checked bag on a flight from Miami to Medellin, Colombia. Count 1 of the indictment charged Adolfo Leon Gomez,3 Hugo Rios 4 and appellant with conspiracy to defraud the Internal Revenue Service by failing to file a United States Customs Form 4790, Report of International Transportation of Currency or Monetary Instruments, in connection with transportation of an amount of United States currency in excess of $10,000 from Miami to Medellin, Colombia.5 18 U.S.C. § 371. Count 2 charged [1129]*1129appellant, Gomez and Rios with the substantive offense of knowingly failing to file the required report, in violation of 31 U.S.C. §§ 5316, 5322.6 18 U.S.C. § 2. Count 3 charged appellant with making a false, fraudulent and fictitious statement to a United States Customs Service agent. Appellant allegedly stated that he was not carrying more than $10,000 in monetary instruments when in fact he was carrying approximately $203,000 in United States currency. 18 U.S.C. § 1001.7
The issues before this court arise from appellant’s motion to suppress the evidence against him as the product of an illegal search. After an evidentiary hearing, the magistrate recommended that all evidence against appellant be suppressed as the fruit of an illegal search; he found the statute granting authority to Customs officers to search outgoing luggage without a search warrant on the basis of “reasonable cause,” 31 U.S.C. § 5317(b), unconstitutional on its face.8 After hearing oral argument on the motion, the district court sustained the government’s objections and reversed the magistrate’s recommendation.
The parties waived their rights under Fed.R.Crim.P. 23(c) to special findings of fact, and the case proceeded to a bench trial on stipulated facts.9 Appellant was convicted on all three counts and sentenced to three concurrent three year sentences and $150 fine.
Initially, the parties dispute the role that the magistrate’s factual findings should play in our decision. Appellant contends that the magistrate’s factual findings are entitled to deference because the district court held no evidentiary hearing and made no factual findings.
We conclude that the magistrate’s findings are not entitled to deference in this case.10 The district court reversed the magistrate’s recommendation without making factual findings.11 The parties stipu[1130]*1130lated for trial to the testimony at the suppression hearing, not to the magistrate’s factual findings.5 ******12 The parties also waived their right to special findings of fact under Fed.R.Crim.P. 23(c).13 Where the defendant waives his right to special findings under Rule 23(c), findings will be implied on appeal in support of the judgment if the evidence, viewed in the light most favorable to the government, warrants them. United States v. Ochoa, 526 F.2d 1278, 1282 n. 6 (5th Cir.1976); United States v. Gant, 691 F.2d 1159, 1163 (5th Cir.1982). See also 8A J. Moore, Moore’s Federal Practice ¶ 23.05[2] (2d ed. 1986). This rule is not altered where the magistrate made findings at a pre-trial suppression hearing, timely objections were made, and the district court made inadequate factual findings. United States v. Lewis, 621 F.2d 1382, 1387 (5th Cir.1980) (where district court made inadequate factual findings in affirming magistrate’s recommendation on suppression issue, appellate court may make its own findings on the basis of the transcript at the suppression hearing before the magistrate), cert. denied, 450 U.S. 935, 101 S.Ct. 1400, 67 L.Ed.2d 370 (1981); United States v. Berry, 670 F.2d 583, 603 n. 25 (5th Cir. Unit B 1982) (en banc) (same). See also United States v. Smith, 543 F.2d 1141, 1145 (5th Cir.1976) (appellate court would make independent review of record, accepting evidence supporting the judgment where conflict exists, when district court made no findings of fact in ruling on suppression issue), cert. denied, 429 U.S. 1110, 97 S.Ct. 1147, 51 L.Ed.2d 564 (1977).
I. FACTS
On May 4, 1985, United States Customs agents at the Miami International Airport decided to investigate an Avianca Airlines flight travelling from Miami to Barranquilla and Medellin, Colombia, to check for compliance with currency declaration laws.14 United States Customs Inspector Charles Headley and another Customs agent were assigned to inspect checked baggage before the baggage was loaded on the aircraft.15 Because the two agents had only about an hour before the flight was to depart, it would have been impossible for them to search all of the 250 to 300 bags that had been checked.
Due to the time and personnel constraints, Agent Headley utilized certain factors that, in the experience of Customs agents, indicated that a bag should be searched. Headley had been told that, in the experience of Customs agents, hard-sided luggage is often used by smugglers to conceal contraband, unlicensed high technology equipment, weapons, or currency because the bags can be equipped with false sides to offer interior concealment. Headley also had been told that bags without legible name identification tags or claim checks were suspicious. Finally, Headley had been informed that heavy bags were more likely to be false-sided suitcases, containing computers or things of that nature. As of May 4, 1985, however, Agent Headley had never personally discovered currency in checked baggage.16
[1131]*1131After about ten minutes of investigating the baggage, Agent Headley noticed a hard-sided American Tourister bag with a baggage claim stub but no name identification tag. Headley lifted the bag and found it to be unusually heavy. Upon discovering that the bag was locked, Headley forced the locks open with one of his pass keys. Inside the bag, Headley discovered clothing, personal belongings, and several foodstuff boxes. Headley felt the boxes but they didn’t feel like they contained foodstuffs. He opened the boxes and found a large quantity of United States currency.
Agent Headley then radioed United States Customs Service Agent John Howe to inform him that Headley had discovered a large amount of United States currency in examining baggage for outgoing Avian-ca flight 063. Headley gave Howe the baggage claim check number for the suitcase that contained the cash.
Howe and several other agents proceeded to the gate area where Avianca flight 063 was to depart forty-five minutes later, and set up for outbound inspection of passengers. The agents placed signs in the gate area stating the currency declaration requirements for individuals transporting in excess of $10,000 in monetary instruments out of the United States.17 One of the agents read the currency declaration requirements several times over the public address system and handed out forms detailing the requirements.18
When none of the passengers came forward to declare currency, Agent Howe positioned himself at the entrance to the jet-way as the flight began boarding. He examined the passengers’ tickets, boarding passes, and passports prior to letting them pass onto the jetway. When appellant approached and handed his. documents to Agent Howe, Howe noticed that the baggage claim check attached to appellant’s ticket bore the same number as the bag that Agent Headley had discovered contained a large amount of United States currency. After returning the documents and allowing appellant to pass onto the jetway, Howe pointed to United States Customs Service Inspector Robert Estrada to indicate to Estrada that appellant was the person they had been waiting for.
Inspector Estrada stopped appellant in the jetway for questioning.19 After identifying himself, Estrada asked to see appellant’s passport. When appellant produced the passport,20 Estrada inquired as to whether appellant heard and understood the announcements regarding currency declaration requirements. Appellant said that he had heard and understood. Appellant produced a Customs leaflet describing the reporting requirements when Estrada asked if he had received a leaflet. Estrada then asked whether appellant was carrying over $10,000 in checks, negotiable bonds or instruments, or any commercial items. Appellant replied, “no, no, Inspector. I work for the airlines and I know the law.” Estrada asked to see the handbag that appellant was carrying. Inside the handbag, Estrada found and opened a sealed white envelope that contained six “smurf” checks21 totaling approximately $22,500.
At that point, Inspector Estrada formally placed appellant under arrest and gave him a Miranda warning. In response to questioning, appellant stated that he was not travelling with anyone else and that Hugo [1132]*1132Rios had given the money to him to transport to Colombia. The agents took appellant downstairs to the Customs office to interview him further. Later, they transported appellant to the downtown Miami Customs office for processing and further questioning.
II. VOID FOR VAGUENESS?
Appellant attacks section 5317(b) both on its face and as applied to him. One of his primary arguments on appeal is that the district court erred in reversing the magistrate’s holding that the statute, granting authority to search luggage on the basis of “reasonable cause,” is void for vagueness. The magistrate found that 31 U.S.C. § 5317(a) requires a search warrant issued upon a showing of probable cause in order for agents to be able to search for monetary instruments being transported in violation of 31 U.S.C. § 5316.22 The magistrate reasoned, however, that subsection (a) could not co-exist with subsection (b) which was added in a 1984 amendment. Subsection (b) grants authority to Customs officers to stop and search without a search warrant any “vehicle, vessel, aircraft, or other conveyance, envelope, or other container, or person entering or departing from the United States,” whenever the officer has “reasonable cause to believe” that a section 5316 violation is occurring.23 The magistrate determined that the “reasonable cause to believe” standard in subsection (b) is not defined in the statute or the legislative history. The magistrate concluded, therefore, that section 5317(b) is void for vagueness because its “irreconcilable inconsistenc[y]” with section 5317(a) does not place a reasonable person on notice of the standards by which his or her actions are governed.
Appellant contends that the statute is unconstitutional under the “second form” of the void for vagueness doctrine because it amounts to an unrestricted delegation of power to Customs officers.24 Appellant cites no case in which the constitutional void for vagueness doctrine has been applied to a non-penal statute regulating the circumstances under which officers may conduct a search. The district court concluded that the doctrine was inapplicable because the statute in question is merely [1133]*1133“a procedural limitation on the authority of Customs.” We need not decide, however, the question of whether a statute of this type may be unconstitutional under the void for vagueness doctrine because we conclude that the statute is not vague.
We find no irreconcilable inconsistency between sections 5317(a) and 5317(b). Section 5317(a) provides a general grant of authority to all treasury agents to search anywhere for violations of section 5316.25 This authority may not be exercised absent a showing of probable cause and a search warrant, United States v. Chemaly, 741 F.2d 1346 (11th Cir.1984), or a valid consent to search. United States v. Rojas, 671 F.2d 159, 166-67 (5th Cir. Unit B 1982).26 In contrast, section 5317(b)’s grant of authority applies only to (1) Customs officers (2) searching “a vehicle, vessel, aircraft, or other conveyance, envelope, or other container, or person” that is (3) entering or departing from the United States.27 A search that meets the conditions of section 5317(b) may be conducted if the Customs officer has “reasonable cause to believe there is a monetary instrument being transported in violation of Section Section 5317(b) is therefore a limited exception to the general rule provided in section 5317(a), and the two subsections do not conflict. 5316.”
In addition, the use of the phrase “reasonable cause to believe” in section 5317(b) does not render the statute constitutionally void for vagueness. The district court read “reasonable cause to believe” to mean “reasonable suspicion to search.” This interpretation is supported by United States v. Arends, 776 F.2d 262, 264 n. 1 (11th Cir.1985), where we declared in dictum that under section 5317(b), “the government must have reasonable suspicion to search individuals or objects for currency violations.” The legislative history indicates that the section was clearly intended to authorize searches on the basis of less than probable cause,28 and Supreme Court precedent suggests that “new” fourth amendment standards other than probable cause and reasonable suspicion are disfavored.29 We conclude that the “reasonable cause to believe” requirement in section 5317(b) requires reasonable suspicion to search and that this standard is not vague.30
[1134]*1134III. APPLICATION OF SECTION 5317(b)
Having determined the correct standard by which the legality of a search under section 5317(b) must be determined, we next address whether the standard was met in this case. We first examine the legality of Agent Headley’s search of appellant’s luggage, and then determine whether the agents’ subsequent actions in detaining appellant in the jetway and searching appellant’s carry-on bag violated appellant’s fourth amendment rights.
Agent Headley’s search of appellant’s checked suitcase can only be sustained if the agent reasonably suspected that appellant’s suitcase was transporting undeclared currency out of the United States in violation of section 5316. Reasonable suspicion to search requires a “particularized and objective basis for suspecting” a section 5316 violation. United States v. Montoya de Hernandez, 473 U.S. 531, 105 S.Ct. 3304, 3311, 87 L.Ed.2d 381 (1985); United States v. Cortez, 449 U.S. 411, 417, 101 S.Ct. 690, 695, 66 L.Ed.2d 621 (1981).
Although the question is admittedly close, we conclude that Agent Headley had a reasonable and articulable basis for believing that appellant’s suitcase contained undeclared currency in violation of section 5316. Agent Headley relied upon three characteristics of appellant’s bag in electing to search the suitcase’s contents. These factors were: (1) the fact that the suitcase was hard-sided; (2) the absence of a name identification tag; and (3) the excessive weight of the bag. Each of the factors is consistent, in the experience of Customs officers, with an attempt to transport a large amount of undeclared currency out of the United States. Although no one factor would be independently sufficient, we conclude that the presence of all three factors in this case, along with the fact that the bags were being loaded on an Avianca flight from Miami to Colombia, gave the agent sufficient reasonable suspicion to enable him to conduct a lawful search limited to confirming or dispelling the suspicions. See United States v. Cortez, 449 U.S. 411, 418, 101 S.Ct. 690, 695, 66 L.Ed.2d 621 (1981).
The search was also narrowly tailored to the circumstances that justified its initiation. Agent Headley opened appellant’s bag with a pass key and inspected the contents in an area out of public view. Upon discovering the currency, he placed the suitcase back on its way to be loaded on board the aircraft. The search was therefore a limited intrusion upon appellant’s privacy interests.
Our construction of section 5317(b)’s grant of authority to search on the basis of “reasonable cause to believe” that a section 5316 violation is occurring is consistent with congressional intent. In enacting section 5317(b) as a part of the Comprehensive Crime Control Act of 1984, Congress sought to grant special authority to Customs officers in border areas to search for currency, the “life blood of organized crime.”31 See United States v. Arends, 776 F.2d 262, 265 (11th Cir.1985) (Hill, J., specially concurring). If section 5317(b) is read as requiring a further basis for suspicion prior to enabling Customs officers to search a checked bag, the intent of subsection (b) would be largely defeated. Under that construction, unless currency were [1135]*1135protruding from checked luggage, it is difficult to conceive of a situation where Customs officers would have sufficient suspicion to conduct a lawful search of a checked bag without some independent contact with the bag’s owner or an informant’s “tip.” We believe that such independent contact was not intended to be essential in all cases in order for a Customs officer to have reasonable suspicion to search.32
The subsequent detention of appellant in the jetway and search of his carry-on bag were also supported by the statute. Customs agents knew that the claim check attached to appellant’s ticket bore the same number as the claim check attached to the suitcase containing in excess of $200,000 in United States currency. Agents also knew that appellant had not declared this currency despite a variety of announcements explaining the requirements. When appellant stepped onto the jetway preparing to board the plane, he had “unequivocally manifested an intention to leave the United States.” United States v. Rojas, 671 F.2d 159, 163 (5th Cir. Unit B 1982). It follows from our analysis in Rojas that the subsequent stop of appellant and search of his bag was supported by reasonable suspicion:
At the time of the stop [on the jetway], Customs agents had information from a reliable informant that Rojas was carrying $1,000,000 in cash, and the agents knew that she had twice denied this and had refused to fill out a reporting form. These facts constituted reasonable suspicion meriting further investigation.
Id. at 164-65.33
Even if appellant’s detention on the jetway rose to the level of an arrest,34 our analysis in Rojas leads to the conclusion that appellant committed the section 5316 violation at the time he entered the jetway. When appellant insisted that he was not transporting in excess of $10,000 in undeclared currency, “[c]ustoms agents in effect witnessed the crime and hence had probable cause to arrest” appellant. Id. at [1136]*1136165. We conclude, therefore, that the agents’ actions in this case were consistent with section 5317(b) and that the search and seizure was lawful unless section 5317(b) is unconstitutional.
IV. CONSISTENCY WITH THE FOURTH AMENDMENT
It is well established that the fourth amendment constrains the power of Congress to authorize searches and seizures. Almeida-Sanchez v. United States, 413 U.S. 266, 272, 93 S.Ct. 2535, 2539, 37 L.Ed.2d 596 (1973); United States v. Villamonte-Marquez, 462 U.S. 579, 585, 103 S.Ct. 2573, 2578, 77 L.Ed.2d 22 (1983). The Supreme Court has stated that a “cardinal principle” of the fourth amendment is that: “[S]earches conducted outside the judicial process, without prior approval by judge or magistrate, are per se unreasonable under the Fourth Amendment — subject to a few specifically established and well-delineated exceptions.” United States v. Ross, 456 U.S. 798, 825, 102 S.Ct. 2157, 2173, 72 L.Ed.2d 572 (1982); Mincey v. Arizona, 437 U.S. 385, 390, 98 S.Ct. 2408, 2412, 57 L.Ed.2d 290 (1978); Katz v. United States, 389 U.S. 347, 357, 88 S.Ct. 507, 514, 19 L.Ed.2d 576 (1967).35 “[T]he mere fact that law enforcement may be made more efficient can never by itself justify disregard of the Fourth Amendment.” Mincey, 437 U.S. at 393, 98 S.Ct. at 2414.
It is also established that appellant had a reasonable expectation of privacy in his checked luggage. As we stated in United States v. Goldstein, 635 F.2d 356, 361 (5th Cir. Unit B 1981), “when airport security is not involved, every passenger who has luggage checked with an airline enjoys a reasonable expectation of privacy that the contents of that luggage will not be exposed in the absence of consent or a legally obtained warrant.” (emphasis omitted).36 Our conclusion in Goldstein is supported by Torres v. Commonwealth of Puerto Rico, 442 U.S. 465, 99 S.Ct. 2425, 61 L.Ed.2d 1 (1979). In Torres, the appellant took a non-stop flight from Miami to San Juan, Puerto Rico. Upon arriving in Puerto Rico, local police searched Torres’s luggage without probable cause or a warrant. The Supreme Court held that the search violated Torres's fourth amendment rights. Chief Justice Burger wrote for the court:
The search of appellant’s baggage ... did not satisfy the requirements of the Fourth Amendment as we have heretofore construed it. First, the grounds for a search must satisfy objective standards which ensure that the invasion of personal privacy is justified by legitimate governmental interests. The governmental interests to be served in the detection or prevention of crime are subject to traditional standards of probable cause to believe that incriminating evidence will be found. Second, a warrant is normally a prerequisite to a search unless exigent circumstances make compliance with this requirement impossible.
442 U.S. at 471, 99 S.Ct. at 2429-30 (citations omitted).
Section 5317(b) authorizes luggage searches without consent, a warrant, probable cause, any risk to airport security, or exigent circumstances. The government apparently concedes that, unless the “border search exception” to the fourth amendment applies, the measure violates the fourth amendment.
The Supreme Court has discussed the scope of the “border search exception” in the context of incoming persons and property.37 The Court has indicated that the [1137]*1137“border search exception” is based upon the sovereign’s authority to protect itself by examining incoming persons and property.38 The Court has not, however, decided any case involving searches of outgoing persons and property.39 We decline to construe the Court’s general statements of the border search rationale so narrowly as to foreclose the proposition at issue here.
In several prior decisions, this Circuit has reserved the question of whether the border exception extends to departing persons and instrumentalities. See United States v. Arends, 776 F.2d 262, 264 n. 2 (11th Cir.1985); United States v. Chemaly, 741 F.2d 1346, 1351 (11th Cir.1984); United States v. Rojas, 671 F.2d 159, 164 (5th Cir. Unit B 1982). However, the time has come to determine whether Congress may, consistent with the fourth amendment, authorize warrantless searches of persons and property40 departing from the United States on the basis of reasonable suspicion to search.
Every circuit41 that has considered the question has ruled that the rationales for the “border exception” apply both to incoming and outgoing persons and instrumentalities. See United States v. Swarovski, 592 F.2d 131 (2d Cir.1979); United States v. Ajlouny, 629 F.2d 830 (2d Cir.1980); United States v. Udofot, 711 F.2d 831 (8th Cir.), cert. denied, 464 U.S. 896, 104 S.Ct. 245, 78 L.Ed.2d 234 (1983); United States v. Stanley, 545 F.2d 661 (9th Cir.1976); United States v. Duncan, 693 F.2d 971 (9th Cir.1982), cert. denied, 461 U.S. 961, 103 S.Ct. 2436, 77 L.Ed.2d 1321 (1983). The Ninth [1138]*1138Circuit, in Stanley, summarized the rationale for its holding as follows:
[B]oth incoming and outgoing border-crossing searches have several features in common: (1) the government is interested in protecting some interest of United States citizens, such as restriction of illicit international drug trade, (2) there is a likelihood of smuggling attempts at the border, (3) there is difficulty in detecting drug smuggling, (4) the individual is on notice that his privacy may be invaded when he crosses the border, and (5) he will be searched only because of his membership in a morally neutral class.
545 F.2d at 667.
Although we need not decide here whether the “border exception” applies equally in all respects to incoming and outgoing searches at the border, we conclude that Congress may, consistent with the fourth amendment, authorize Customs officers to conduct warrantless searches of persons and property departing the United States on the basis of reasonable suspicion that a currency reporting violation is occurring. The permissibility of a particular law enforcement practice is judged by “balancing its intrusion on the individual’s Fourth Amendment interests against its promotion of legitimate governmental interests.” United States v. Montoya de Hernandez, 473 U.S. 531, 105 S.Ct. 3304, 3309, 87 L.Ed.2d 381 (1985) (quoting United States v. Villamonte-Marquez, 462 U.S. 579, 588, 103 S.Ct. 2573, 2579, 77 L.Ed.2d 22 (1983)).
The governmental interest in stemming the flow of unreported currency out of the United States is substantial.42 Large amounts of undeclared currency departing the United States bear an obvious relationship to the “veritable national crisis in law enforcement”43 caused by smuggling of illicit narcotics and money laundering schemes often associated with organized crime.44 The “long-standing right of the sovereign to protect itself”45 that underlies the traditional rationale for the border search exception is implicated to a substantial degree where the international borders of the United States are penetrated by large sums of undeclared currency departing this country.
Balanced against this governmental interest is the fourth amendment rights of individuals to be free from unreasonable searches and seizures. The statute grants authority for only a limited exception to the fourth amendment warrant and probable cause requirements for a search. Section 5317(b) allows Customs officers to search for section 5316 violations only where reasonable suspicion to search is present; thus searches for section 5316 violations on less than reasonable suspicion remain unlawful. See United States v. Chemaly, 741 F.2d 1346 (11th Cir.1984).
An individual’s expectation of privacy is also less at international borders. United [1139]*1139States v. Montoya de Hernandez, 473 U.S. 531, 105 S.Ct. 3304, 3310, 87 L.Ed.2d 381 (1985). Although an individual may have a more substantial expectation of privacy when departing the country than when entering, individuals attempting to depart from the United States are on notice that they may be questioned and searched. Finally, the fourth amendment balance between the interests of the government and the privacy right of the individual is struck much more favorably to the government at the border. Id.
Balancing these considerations leads us to conclude that section 5317(b) does not authorize unreasonable searches and seizures. Finding that the statute is constitutional both on its face and as applied to appellant, we AFFIRM appellant’s convictions.