BRORBY, Circuit Judge.

Defendants, Beverly and Ronald Joseph Bute ("the Butes"), bring this consolidated appeal challenging the district court's denial of their joint motion to suppress evidence allegedly obtained in violation of the Fourth Amendment. We have jurisdiction under 28 U.S.C. § 1291, and reverse.

I

At roughly 11:00 p.m., on March 20, 1992, Deputy Salt Lake County Sheriff Daniel McConkey began his shift by taking Deputy Cannon, the Deputy he was relieving, home. On the way, both officers noticed an open garage door at 13180 So. 2700 West, Salt Lake County, Utah (the Bute building). Cannon identified the Bute building as an old honey manufacturing plant, though McConkey testified he was not aware of the building's present use. McConkey described it as a "[c]inder block building, [with] a small window, which would be on the front of the building, on the south side, and there's a walk door and there's a garage door next to that." The building was owned by Gene Fisher who had rented it to the Butes, though the officers were not aware of these facts.

The open garage door aroused some suspicion in McConkey because he had never seen anyone around the building before and never noticed the garage door was routinely left open. Nevertheless, McConkey did not stop but rather, continued to building. While in his vehicle, McConkey shined his bright lights and search light into the garage, illuminating it. He testified at the suppression hearing from that vantage point he could see the garage contained some shelves on one wall, a chair, and what he described as "normal garage type stuff, gas cans." There was no vehicle in the garage, no indication that anyone was in or around the Bute building, and no sign of forced entry.

Nevertheless, and without articulating any reason, he suspected the building might have been vandalized or burglarized earlier and decided to enter the building in order to search for any indication of burglary or vandalism. He radioed to dispatch informing them he had "an open door" and "would be out to check it." He did not, however, request a backup as is customary when an officer suspects a possible burglary or other threat to property in progress.

When McConkey entered the building through the garage door, he noticed what he described as a "very pungent" and unusual odor which he could not identify. Along a single wall in the garage were three doors, all of which were closed or only slightly ajar. He opened the first door, shined his flashlight inside, and saw it was a furnace room. He moved on to the second door, opened it, and saw a living-type area which contained a bed or sofa, chairs, a table with an ashtray, and a television. He called out to see if anyone was there but got no response. He then moved to the third door. He observed a room with some glass beakers and bottles, some of which had rubber tubing connected to them, and a television monitor on the floor. McConkey testified upon observing the contents behind door number three, he suspected he had found a "lab of some sort." However, he was unable to identify what sort of lab it was or connect the lab to any criminal activity.

Once outside, McConkey called for a backup officer. Sergeant Wood responded and McConkey informed him of what his search of the building had revealed. The two then reentered the building and went immediately to door number three. After observing the lab, the officers left. However, because the two were still apparently unaware of what it was they had found, they contacted metro narcotics as well as a hazardous materials team. The narcotics team arrived first, entered the building, and observed the lab. When the hazardous materials team arrived, they did the same. At no time did any of the officers attempt to locate or ascertain the owner or occupant of the building.

Eventually, a search warrant was obtained based on the information provided by McConkey, Sergeant Wood, and the metro narcotics officers. The search executed pursuant to that warrant revealed the lab was used for the manufacture of methamphetamines. Subsequently, additional search warrants were obtained and executed at various locations including the nearby residence of the Butes.

The Butes were charged, and later indicted, for possession of methamphetamine with intent to distribute and manufacturing methamphetamine, both in violation of 21 U.S.C. § 841(a)(1). The Butes filed a joint motion to suppress the evidence seized from the Bute building and any fruits of that evidence claiming the initial search was illegal. A hearing was held before Magistrate Judge Ronald N. Boyce who issued a report and recommendation denying the Butes' motion. The Butes then filed objections to the report and recommendation with the district court. After argument, the court issued an order adopting the report and recommendation of the magistrate judge.

The Butes entered conditional pleas of guilty and now bring this appeal arguing the magistrate judge's report and recommendation adopted a novel Fourth Amendment analysis that cannot be squared with the precedent of the United States Supreme Court or the precedent of this court. Application of the appropriate legal standard, they argue, requires reversal.

When reviewing a district court's denial of a motion to suppress, the trial court's findings of fact are accepted unless clearly erroneous. United States v. Pena, 920 F.2d 1509, 1513 (10th Cir. 1990), cert. denied, 501 U.S. 1207, 111 S.Ct. 2802, 115 L.Ed.2d 975 (1991). The ultimate question of whether a search is reasonable under the Fourth Amendment is a question of law which we review de novo. United States v. McKinnell, 888 F.2d 669, 672 (10th Cir. 1989). "[W]hen the defendant challenges a warrantless search or seizure the government carries the burden of justifying the agents' actions." United States v. Maestas, 2 F.3d 1485, 1491 (10th Cir. 1993); see also Vale v. Louisiana, 399 U.S. 30, 34, 90 S.Ct. 1969, 1971, 26 L.Ed.2d 409 (1970).

II

The magistrate judge concluded none of the recognized exceptions to the warrant requirement offered by the government applied under the facts of this case. Nevertheless, the magistrate judge went on to analyze the constitutionality of McConkey's search under a general "reasonableness" test, taking into account the totality of the circumstances. Under that standard, the magistrate judge concluded the search was reasonable, and therefore, constitutionally permissible.

Under the Fourth Amendment to the United States Constitution, "`one governing principle, justified by history and by current experience, has consistently been followed: except in certain carefully defined classes of cases, a search of private property without proper consent is "unreasonable" unless it has been authorized by a valid search warrant.'" Michigan v. Tyler, 436 U.S. 499, 506, 98 S.Ct. 1942, 1948, 56 L.Ed.2d 486 (1978) (emphasis added) (quoting Camara v. Municipal Court, 387 U.S. 523, 528-29, 87 S.Ct. 1727, 1730-31, 18 L.Ed.2d 930 (1966)); see also Katz v. United States, 389 U.S. 347, 357, 88 S.Ct. 507, 514, 19 L.Ed.2d 576 (1967) (warrantless searches "are per se unreasonable under the Fourth Amendment — subject only to a few specifically established and well-delineated exceptions." (footnotes omitted)); United States v. Anderson, 981 F.2d 1560, 1567 (10th Cir. 1992). Among those "well-delineated" exceptions to the warrant requirement are situations in which various forms of exigency exist, see California v. Carney, 471 U.S. 386, 105 S.Ct. 2066, 85 L.Ed.2d 406 (1985) (need to detain a fleeing vehicle); Mincey v. Arizona, 437 U.S. 385, 98 S.Ct. 2408, 57 L.Ed.2d 290 (1978) (individual in need of emergency aid and assistance); Vale v. Louisiana, 399 U.S. 30, 90 S.Ct. 1969, 26 L.Ed.2d 409 (1970) (need to prevent destruction of contraband). Also included are stop and frisk searches, Terry v. Ohio, 392 U.S. 1, 88 S.Ct. 1868, 20 L.Ed.2d 889 (1968), and searches pursuant to voluntary consent, Schneckloth v. Bustamonte, 412 U.S. 218, 93 S.Ct. 2041, 36 L.Ed.2d 854 (1973).

While the magistrate judge was correct in observing that "reasonableness," as the text of the Fourth Amendment indicates, is the touchstone for determining the constitutionality of a search, see Florida v. Jimeno, 500 U.S. 248, 250, 111 S.Ct. 1801, 1803, 114 L.Ed.2d 297 (1991); Cady v. Dombrowski, 413 U.S. 433, 439, 93 S.Ct. 2523, 2527, 37 L.Ed.2d 706 (1973), the precedent of the Supreme Court and this circuit is quite clear that a warrantless search is reasonable only when it falls within one of the clearly defined exceptions to the warrant requirement. See Jimeno, 500 U.S. at 250-51, 111 S.Ct. at 1803. As such, precedent neither establishes nor condones application of an amorphous "reasonableness" test to determine the constitutionality of a warrantless search.

To the extent the magistrate judge's report can be read as an extension of Cady, we are of the opinion that the principle of Cady is inapplicable here. In Cady, the Supreme Court held that Wisconsin police officers who had arrested a Chicago police officer for drunk driving did not violate the Fourth Amendment in searching the suspect's car for a firearm. Cady, 413 U.S. at 447, 93 S.Ct. at 2531. Noting that the arresting officers believed that Chicago police were required to carry a service revolver with them at all times, the Court concluded the search was incident to the caretaking function of the local police to protect "the safety of the general public who might be endangered if an intruder removed a revolver from the trunk of the vehicle." Id. at 447, 93 S.Ct. at 2531. In short, the search was justified because the officers reasonably believed that the car contained a gun, id. at 447-48, 93 S.Ct. at 2531, and was constitutionally permissible in light of "[t]he Court's previous recognition of the distinction between motor vehicles and dwelling places" id. at 447, 93 S.Ct. at 2531. See, e.g., Chambers v. Maroney, 399 U.S. 42, 52, 90 S.Ct. 1975, 1981, 26 L.Ed.2d 419 (1970); Cooper v. California, 386 U.S. 58, 59, 87 S.Ct. 788, 789, 17 L.Ed.2d 730 (1967).

As the Ninth Circuit has recognized, " Cady clearly turned on the `"constitutional difference'" between searching a house and searching an automobile." United States v. Erickson, 991 F.2d 529, 532 (9th Cir. 1993) (quoting Cady, 413 U.S. at 439, 93 S.Ct. at 2527). As such, the Erickson court held Cady restricted the community caretaking exception to searches not involving homes or offices. Erickson, 991 F.2d at 532. In doing so, it cited with approval the Seventh Circuit's refusal to extend the community caretaking exception to the warrantless search of a warehouse. Id. (citing United States v. Pichany, 687 F.2d 204, 209 (7th Cir. 1982)). The Seventh Circuit declined to extend Cady to the warrantless search of a warehouse on the grounds that:

[T]he plain import from the language of [ Cady] is that the Supreme Court did not intend to create a broad exception to the Fourth Amendment warrant requirement to apply whenever the police are acting in an "investigative," rather than a "criminal" function. The Court intended to confine the holding to the automobile exception and to foreclose an expansive construction of the decision allowing warrantless searches of private homes or businesses.

Pichany, 687 F.2d at 208-09.

We agree with this line of authority holding the community caretaking exception to the warrant requirement is applicable only in cases involving automobile searches. Thus, we conclude the community caretaking exception to the warrant requirement is inapplicable under the facts of this case.

III

On appeal, the prosecution argues McConkey's search of the Bute building was justified under the so-called "security check" exception to the warrant requirement as well as the exigency recognized for the protection of property. For the reasons that follow, we decline to recognize the security check exception to the warrant requirement of the Fourth Amendment and conclude that the protection of property exception is inapplicable under the facts of this case.

A

At least three state courts have held that law enforcement officials need not obtain a warrant in order to enter commercial premises, for the purposes of securing them, when they are found to be unlocked or otherwise open at night. The leading case, Alaska v. Myers, 601 P.2d 239 (Alaska 1979), involved two officers who routinely walked through the downtown area of Juneau checking for unlocked doors at commercial establishments. At 2:30 a.m., they observed an open door at the end of corridor leading from a back alley. The officers entered the building (a movie theater) and observed individuals with cocaine and drug paraphernalia. Id. at 241.

In permitting use of the evidence gathered as a result of the search, the Alaska Supreme Court noted none of the previously recognized exceptions to the warrant requirement were applicable under the facts. In recognizing a new exception to the warrant requirement, the court held:

[L]aw enforcement personnel may enter commercial premises without a warrant only when, pursuant to a routine after-hours security check undertaken to protect the interests of the property owner, it is discovered that the security of the premises is in jeopardy, and only when there is no reason to believe that the owner would not consent to such an entry.

Id. at 244.

In California v. Parra, 30 Cal.App.3d 729, 106 Cal.Rptr. 531, cert. denied, 414 U.S. 1116, 94 S.Ct. 849, 38 L.Ed.2d 743 (1973), the California Court of Appeals upheld the warrantless search of commercial building motivated by a desire to secure the premises. Id., 106 Cal.Rptr. at 533. The officer, responding to an "open door" call, entered the premises and in an effort to discover the owner of the business, searched through papers he found on the top of a desk. Finding nothing, he opened the desk drawers looking for information concerning the proprietor of the business. Instead, he found heroin.

The California court upheld the officer's entry on the grounds it would not have constituted a trespass under the law of torts, see id. at 533 (citing Restatement (Second) of Torts § 197) (2d ed.), and thus, the officer's presence in the shop was "privileged." Parra, 106 Cal.Rptr. at 533. In reaching this conclusion, however, the court did not mention the Fourth Amendment or the analogous provision of the California Constitution.

Similarly, in Illinois v. Gardner, 121 Ill. App.3d 464, 76 Ill.Dec. 761, 459 N.E.2d 676 (1984), as part of a routine check of businesses an officer discovered an open door to an automobile repair shop at 4:00 a.m. Following departmental policy, he entered the premises in order to search for intruders and ascertain the owner of the business. Id., 76 Ill.Dec. at 763, 459 N.E.2d at 678. Once inside, he observed a vehicle that was later determined to be stolen.

Relying on Myers and Parra, the Illinois Court of Appeals concluded that "law enforcement officials may enter an unsecured or unlocked commercial establishment during a nighttime security check to secure the premises and may take necessary measures to ascertain the identity of the proprietor." Gardner, 76 Ill.Dec. at 765-66, 459 N.E.2d at 680-81.

The Fourth Amendment protects an individual's reasonable expectation of privacy in commercial premises. See, e.g., Marshall v. Barlow's, Inc., 436 U.S. 307, 98 S.Ct. 1816, 56 L.Ed.2d 305 (1978); See v. City of Seattle, 387 U.S. 541, 543, 87 S.Ct. 1737, 1739, 18 L.Ed.2d 943 (1967) ("The businessman, like the occupant of a residence, has the constitutional right to go about his business free from unreasonable official entries upon his private commercial property."); United States v. Chavez, 812 F.2d 1295, 1299 (10th Cir. 1987). While it may be said as a general rule that there is a lesser expectation of privacy in commercial as contrasted with residential buildings, cf. Payton v. New York, 445 U.S. 573, 589-90, 100 S.Ct. 1371, 1381-82, 63 L.Ed.2d 639 (1980), classifying a building as "commercial" is not dispositive as to the level of privacy that attaches to such premises. On the contrary, the reasonable expectation of privacy in any given property turns on the particular nature and circumstances surrounding the place to be searched. See, e.g., Rakas v. Illinois, 439 U.S. 128, 152-53, 99 S.Ct. 421, 435, 58 L.Ed.2d 387 (1978); United States v. Chadwick, 433 U.S. 1, 11-12, 97 S.Ct. 2476, 2483-84, 53 L.Ed.2d 538 (1977).

In our judgment, it is beyond question that some commercial properties are reasonably accorded a greater level of privacy than others. For instance, if a proprietor has made a general public invitation to enter the premises, there would be a lesser expectation of privacy than in a commercial building that is not open to the public, such as a warehouse. As such, a lesser expectation of privacy likely would attach to the showroom of a car dealership than to a law office where guarded confidential files are kept or a warehouse in which the public is neither invited nor allowed. See Wayne R. LaFave Jerold H. Israel, Criminal Procedure § 3.2(e) (1985) ("Law enforcement officials may enter commercial premises at the times they are open to the public . . . [but may not] enter without consent premises to which the public at large does not have access."). Similarly, there is a lesser expectation of privacy in commercial premises open to the public during business hours as opposed to after hours when no employees are present. United States v. Swart, 679 F.2d 698, 701 (7th Cir. 1982).

The recognition that not all commercial establishments carry the same reasonable expectation of privacy creates an obvious problem for the security check exception to the warrant requirement. Indeed, this difficulty is even one that has been recognized by some courts that have adopted the exception. For instance, the Alaska Supreme Court in Myers correctly recognized that "[e]xpectations of privacy are not all of the same intensity. . . . Both subjectively and in society's judgment as to what is reasonable, distinctions may be made in the varying degrees of privacy retained in different places and objects." Myers, 601 P.2d at 242 (footnotes omitted). We also agree with the observation that "[i]ndividual proprietors who, for any number of legitimate reasons, may not desire even the most cursory searches of their business premises at any time, are entitled to have their right to such privacy protected." Id. at 243.

Yet the security check exception applies to all commercial establishments found unsecured — it makes no accommodation for the particular nature and circumstances surrounding individual buildings. Given this fact, we are of the opinion that the rule of Myers falters under the burden of its own reasoning. The security check exception to the warrant requirement permits entry onto premises based solely on the fact that a door is open or unlocked at night. There are no exceptions. As such, we have little difficulty concluding that the adoption of such a wholesale exception to the warrant requirement of the Fourth Amendment requires an unjustifiably simplistic conception of commercial property and the relative expectations of privacy that attach thereto. Accordingly, we decline to adopt the security check exception advanced by the government.

B

The government next argues McConkey's entry into the Bute building was justified under the protection of property exigency recognized in Tyler, 436 U.S. 499, 98 S.Ct. 1942. We agree with the government's admission that Tyler is not directly on point, but disagree with its contention that the underlying principle recognized in Tyler is broad enough to render the search at issue constitutionally permissible.

In Tyler, fire department officials responded to a report of a burning building. In the course of their efforts to combat the blaze, the firefighters observed two plastic containers of flammable liquid inside the building. The official responsible for determining the cause of the blaze was informed of this fact and, suspecting arson, entered the building to examine the containers and photograph the interior of the building. The official was forced to abandon his efforts due to excessive smoke and steam. After the fire was extinguished, the firefighters left the scene. They removed the two containers and brought them to the fire station for safekeeping. See Tyler, 436 U.S. at 501-02, 98 S.Ct. at 1945-46. No consent had been obtained for any entry into the building or for the removal of the containers. The defendants, who were tried for conspiracy to burn real property, moved to have all the evidence suppressed on the grounds that it was obtained without a warrant and without their consent.

The Supreme Court first concluded the invasion of privacy that results from a fire official's entry into a commercial establishment is "clearly within the protection of the Fourth Amendment." Id. at 505, 98 S.Ct. at 1947. However, the Court held "[a] burning building clearly presents an exigency of sufficient proportions to render a warrantless entry `reasonable.' Indeed, it would defy reason to suppose that firemen must secure a warrant or consent before entering a burning structure to put out the blaze." Id. at 509, 98 S.Ct. at 1950. Thus, the Court concluded the initial entry into the building was reasonable and the Fourth Amendment was not violated by the seizure of evidence of arson in plain view. Id.

While Tyler establishes the general principle that the need to protect property may justify a warrantless entry of premises, it is equally clear the application of that principle rests on a clear showing of an immediate need to protect property. The immediacy of the need for protection was so obvious in Tyler it required no elaboration or explanation.

Unlike a burning building, however, no evidence of any emergency or immediate threat to the Bute building was shown here. To put it simply, a burning building is not the same as an open garage door in terms of the immediacy of threat each presents. As such, the exigency identified in Tyler for the protection of property against an immediate threat is inapplicable here.

United States v. Moskow, 588 F.2d 882 (3rd Cir. 1978), similarly is inapplicable. In Moskow, the police, "responding to specific information of a surreptitious entry into a vacant building at a late hour of the night," id. at 892, approached the building where they detected a strong odor of gasoline. The court held the fumes, taken together with the possibility that the reported intruder was either still in the building or had left a fuse or delay mechanism behind to ignite the gasoline, constituted an exigent circumstance justifying the warrantless entry into the building in order to protect the property. Id. at 892-93.

In contrast, McConkey had no information regarding a surreptitious entry into the Bute building. In addition, there was no indication whatsoever that an intruder was in the building or had left behind anything which posed a threat to McConkey or anyone else. In fact, McConkey testified he did not think anyone was in or around the building. He simply had a hunch that criminal activity might have occurred.

The government suggests the odor of gasoline in Moskow is analogous to the strong odor McConkey perceived upon entering the Bute building — both warranting further investigation as to source and possible danger created as a result. However, McConkey did not smell the odor from the Bute building until after he had entered it. The question we are confronted with here is whether his initial entry was constitutionally permissible. As such, anything he may have found or perceived after his entry is irrelevant to our inquiry as information obtained after the entry obviously cannot serve to justify entry in the first place.

The holdings of Tyler and Moskow unquestionably support the proposition that in some circumstances, the need to preserve and protect private property may create an exigency justifying the warrantless search of property. We are of the opinion that no such exigency existed here.

In this respect, United States v. Moss, 963 F.2d 673 (4th Cir. 1992), is instructive. In Moss, an officer of the United States Forest Service investigated an illegally parked car blocking access to a road. He approached a forest service cabin where he thought the owner of the vehicle might have been. He observed there was no lock on the cabin door and saw fresh bike tracks around the cabin. Id. at 675. Based on these facts, he entered the cabin out of three concerns: he thought the cabin may have been broken into; he wanted to locate the owner of the illegally parked vehicle; and he was concerned that the owner of the car might be lost, injured, or dead. Id.

The Fourth Circuit addressed the government's argument that the entry of the cabin was justified to protect persons or property from immediately threatened harm. The court recognized the protection of property may constitute an exigency sufficient to permit police to "enter premises without warrants for such emergency purposes as aiding in firefighting, giving first aid to people in distress, protecting persons or property from threatened harm, and the like." Id. at 678.

"To invoke this so-called `emergency doctrine,'" the court held, "the person making entry must have had an objectively reasonable belief that an emergency existed that required immediate entry to render assistance or prevent harm to persons or property within." Id. (citing Wayne v. United States, 318 F.2d 205, 211-12 (D.C. Cir.) (plurality opinion), cert. denied, 375 U.S. 860, 84 S.Ct. 125, 11 L.Ed.2d 86 (1963); Root v. Gauper, 438 F.2d 361 (8th Cir. 1971)); see also Smith, 797 F.2d at 840 ("the law enforcement officers must have reasonable grounds to believe that there is immediate need to protect their lives or others or their property or that of others"). The Moss court concluded while the officer's motivations were laudable, there was nothing about the circumstances presented supporting the officer's impression that an immediate threat to person or property existed, and therefore, the warrantless entry of the cabin was unreasonable. Id. at 840-41.

The same conclusion holds true under the facts of this case. We simply cannot accept the notion that an open door of a commercial building at night is, in and of itself, an occurrence that reasonably and objectively creates the impression of an immediate threat to person or property as to justify a warrantless search of the premises. McConkey observed an open garage door at a commercial establishment at 11:00 p.m. Whatever suspicion he had regarding the security of the building, it was not so great as to distract him from taking Cannon home. He did not know if the building was commercial, residential, or abandoned. He was ignorant of the building's current use and thus could not have known if the commercial activity potentially being conducted there required activity at night. While McConkey testified there was no indication that anybody was in the building, he could not have known for sure. He did not knock on the walk-up door to see if anyone would answer, nor did he attempt to reach any possible occupants of the building by telephone (as was departmental practice with "open door" inquiries). Rather, he simply observed a door to a commercial building was open and based on that fact, and that fact alone, decided to enter the building and search it for indicia of burglary or vandalism. While he suspected the building might have been vandalized or burglarized earlier, there was nothing to indicate that was the case apart from the open garage. Illuminating the garage, which undoubtedly was legal for him to do as it was open for all to see, see Florida v. Riley, 488 U.S. 445, 109 S.Ct. 693, 102 L.Ed.2d 835 (1989), revealed no evidence of foul play.

Based on these facts, we have little difficulty concluding whatever degree of suspicion or concern the open door may have reasonably aroused in McConkey, that suspicion falls far short of that needed to justify the warrantless entry into the Bute building. Nothing known to McConkey prior to his search supports an objective, reasonable belief that an emergency existed requiring the immediate entry into the Bute building to prevent harm to the building or its contents. To hold otherwise would require this court to either adopt the security check exception to the warrant requirement or stretch the principle of Tyler far beyond its intended and logical reach. This, we decline to do. Accordingly, we hold McConkey's warrantless search of the Bute building violated the Fourth Amendment's prohibition against unreasonable searches and seizures.

IV

In so holding, we are mindful both of an officer's desire to protect the citizens and property on his or her patrol and the public's expectation regarding the protection of commercial property. In holding as we do, we do not suggest an officer can never enter commercial premises that are left open at night. We simply conclude a warrantless entry only is permitted under the Fourth Amendment when the officer has an objectively reasonable belief that an emergency exists requiring immediate entry to render assistance or prevent harm to persons or property within. While the infinite array of facts that may satisfy this requirement must be assessed on a case-by-case basis, it is clear that observing an open and unsecured building, without more, does not. In our judgment, the Fourth Amendment rights of all citizens outweigh the (lesser) expectations of some business owners that law enforcement authorities will enter and secure commercial premises found open at night.

The evidence seized as a result of McConkey's unconstitutional search of the Bute building must be suppressed. Therefore, the ruling of the district court is REVERSED and the case remanded with instructions to the trial court to grant the motion to suppress and for such other and further proceedings as may be just and proper.