George F. Robinson and Elisa K. Robinson (collectively, “the Robinsons”) appeal their convictions for contributing to the delinquency of a minor, a violation of Code § 18.2-371. The Robinsons argue on appeal that the trial court erred in denying their motions to suppress, contending that, because the investigating police officer was located in the curtilage of their home when he witnessed the illicit activity, the resulting search violated their Fourth Amendment right to be free from unreasonable searches and seizures. For the following reasons, we disagree and affirm their convictions.
I. BACKGROUND
In accord with our usual standard of review, on the appeal of a denial of a motion to suppress, we view the evidence and all reasonable inferences flowing from the evidence in a light most favorable to the Commonwealth, the party prevailing below. Garcia v. Commonwealth, 40 Va.App. 184, 189, 578 S.E.2d 97, 99 (2003); Sabo v. Commonwealth, 38 Va.App. 63, 69, 561 S.E.2d 761, 764 (2002).
On August 16, 2002, the Albemarle County Police Department received three separate telephone calls reporting an alleged underage drinking party at the Robinsons’ home. Corporal Scott Cox was dispatched to investigate these allegations, and he arrived at the Robinsons’ home at approximately 11:00 p.m. From the state road in front of the house, Cox could see ten to twenty cars parked on the state road, as well as two to three parked cars on the left-hand side of the driveway. From that position, Cox could also see the house, the front porch, the front door, and the front yard, although *601he could not see the backyard or the entire driveway. The floodlights above the front door were turned on, and the lights along the sidewalk leading to the front door were also turned on.
Cox, who was driving a marked police car with its headlights on, turned into the driveway and started to drive towards the house. While proceeding up the driveway, Cox saw several additional parked vehicles near the right side of the driveway, as well as “several parked vehicles near the side of the house” straight in front of him.
Cox continued up the driveway in his police car. From his position inside the police car, he began to see some “activity” in the backyard. Before reaching the point where the walkway to the front door intersects with the Robinsons’ driveway, Cox saw two individuals holding clear beer bottles. The individuals, both of whom appeared to be underage, were standing by a pine tree about seven or eight yards away from Cox’s police car. The two juveniles “looked at [Cox], looked at the house, yelled ‘cops,’ dropped the beer bottles, and ran down a fence line toward the woods.” Cox pulled his police car behind one of the parked cars and looked to his left. From that vantage point, “[h]e saw juveniles running toward the woods.” Also, “[h]e could see a patio table covered with beer bottles and noticed beer bottles strewn about the backyard.” Cox then got out of his car, “yelled for people to stop running, and radioed other officers who were waiting off the property that kids were running east into the woods.”
The Robinsons were arrested and charged with nineteen counts of contributing to the delinquency of a minor. Both parties filed a motion to suppress, contending that Cox was unlawfully present on their property when he viewed the illicit activity.
At the suppression hearing, several photographs were introduced depicting the layout of the Robinsons’ premises. According to the photographs, the driveway originates from the state road in front of the house. The driveway then splits into two paths. Both paths continue towards the house, and they *602both bend towards the right. The two branches of the driveway merge back into a single driveway near the front, right-hand corner of the house. The house is positioned entirely to the left of the driveway.
Also, a lighted sidewalk leads from the driveway to the front door of the Robinsons’ home. This sidewalk intersects with the driveway just past the area where the two branches of the driveway reunite. A large bush has been planted in front of the sidewalk at the point where the sidewalk intersects with the driveway, shielding a portion of the sidewalk from view. Other than walking across the grass in the front yard, the driveway and connecting sidewalk serve as the only means of apparent pedestrian access to the front door of the house.
Where the driveway paths are divergent, the area between the two branches forms an “island” containing numerous trees. These trees, along with the general rightward bend of the driveway, shield the garage, backyard, and a large portion of the driveway from public view. The portion of the driveway shielded from public view includes the bush and the area where the front sidewalk intersects with the driveway.
At the suppression hearing, Cox testified that his police car was next to the bush in the driveway when he “clearly” saw “two male juveniles standing on the other side of the tree holding beer bottles.” To clarify the position in the driveway from which the officer observed the juveniles, the trial court asked Cox, “So you were at the bush when you saw the two individuals?” Cox responded, “That’s right.”
Cox was asked repeatedly on cross-examination whether he entered the driveway for the purpose of knocking on the front door to speak with an occupant of the house. Each time Cox was asked the question, he responded that he entered the property to “investigate.” Cox further responded in the affirmative to the following question: “Isn’t it correct that you have described the situation you were hoping to observe as the effect when you flick on a light in a dark kitchen, and the cockroaches scatter?” Cox was also asked, “So you were looking for a reaction of people scattering to confirm your *603suspicion that you had an underage drinking party?” Cox responded, “Right.”
By letter opinion dated August 4, 2003, the trial court denied the Robinsons’ motions to suppress. In its written opinion, the trial court observed that Cox “planned to enter the property to investigate the allegations of underage consumption of alcohol.” The trial court also observed that, “[a]s Cox went down the driveway, he could not see the backyard or the garage,” but that “[h]e could see the house, the front yard, and the front porch.” Additionally, the trial court found that “[t]here were no signs posted” — such as a “no trespassing” sign — at the entrance to the driveway.
Based on this evidence, the trial court found that the Robinsons’ driveway was not part of the curtilage of the house and, therefore, concluded that “Cox’s presence there [did] not implicate the Fourth Amendment.” The court additionally found that Cox’s presence in the Robinsons’ driveway was justified by the officer’s right to conduct a “knock and talk,” that is, to approach a home and knock on the front door to speak with an occupant. Under either of the preceding rationales, the trial court concluded that “Cox was in a lawful place in the driveway” when he observed the two juveniles drinking beer, and his observations were therefore admissible pursuant to the plain view exception to the warrant requirement. Accordingly, the trial court denied the Robinsons’ motions to suppress.
The Robinsons were subsequently convicted of nine counts of contributing to the delinquency of a minor, and the trial court sentenced each defendant to six months in jail, three months suspended, on each count. The trial court ordered the sentences to run consecutively, resulting in active jail time of twenty-seven months for each defendant. The Robinsons appeal.
II. ANALYSIS
Although “ ‘[w]e are bound by the trial court’s findings of historical fact unless ‘plainly wrong’ or without evi*604dence to support them,’ ... we review de novo the trial court’s application of legal standards ... to the particular facts of the case.” McCracken v. Commonwealth, 39 Va.App. 254, 258, 572 S.E.2d 493, 495 (2002) (en banc) (quoting McGee v. Commonwealth, 25 Va.App. 193, 198, 487 S.E.2d 259, 261 (1997) (en banc)) (citing Ornelas v. United States, 517 U.S. 690, 699, 116 S.Ct. 1657, 1663, 134 L.Ed.2d 911 (1996)). Further, “[i]n reviewing a trial court’s denial of a motion to suppress, ‘the burden is upon [the appellant] to show that the ruling ... constituted reversible error.’ ” McGee, 25 Va.App. at 197, 487 S.E.2d at 261 (quoting Fore v. Commonwealth, 220 Va. 1007, 1010, 265 S.E.2d 729, 731 (1980)).
Whether a defendant has a reasonable expectation of privacy in the item seized or the place searched is a mixed question of law and fact. That is, we are bound by the trial court’s underlying findings of fact, but we review de novo the ultimate determination of whether the Fourth Amendment applies under the circumstances of this case. See Sharpe v. Commonwealth, 44 Va.App. 448, 454, 605 S.E.2d 346, 349 (2004) (“[W]e review de novo the trial court’s application of defined legal standards such as whether a defendant had a reasonable expectation of privacy sufficient to permit him to raise a Fourth Amendment challenge to a search.”).
A. Cox Was On the Curtilage When He Observed the Juveniles Drinking Beer
The Robinsons contend that Cox conducted an unconstitutional search because the place from which Cox observed the juveniles drinking beer was a part of the curtilage of their home. Although we agree that Cox observed the juveniles drinking beer from within the curtilage of the Robinsons’ home and the trial court erred in concluding otherwise, that determination will not end our inquiry. See Part II.B, infra.
Because homeowners possess a reasonable expectation of privacy in the curtilage surrounding their homes, Oliver v. United States, 466 U.S. 170, 180, 104 S.Ct. 1735, 1742, 80 L.Ed.2d 214 (1984), “the curtilage ... warrants the *605Fourth Amendment protections that attach to the home.” Id.; see also Jefferson v. Commonwealth, 27 Va.App. 1, 15, 497 S.E.2d 474, 481 (1998) (“Consistent with the common law understanding of the extent of the ‘home,’ the Supreme Court has held that the Fourth Amendment protections that apply to the house also apply to the ‘curtilage’ of the house.”). Because the Fourth Amendment protects the curtilage to the same extent as the home, a police officer may not enter the curtilage without a warrant, exigent circumstances, or pursuant to an express or implied invitation from the occupant. See Payton v. New York, 445 U.S. 573, 589-90, 100 S.Ct. 1371, 1381-82, 63 L.Ed.2d 639 (1980) (“To be arrested in the home involves not only the invasion attendant to all arrests but also an invasion of the sanctity of the home. This is simply too substantial an invasion to allow without a warrant, at least in the absence of exigent circumstances ----” (internal quotations omitted)).
Generally, the curtilage of a home is the “area around the home to which the activity of home life extends.” Oliver, 466 U.S. at 180, 104 S.Ct. at 1742; see also Wellford v. Commonwealth, 227 Va. 297, 301, 315 S.E.2d 235, 238 (1984) (defining “curtilage” as the “space necessary and convenient, habitually used for family purposes and the carrying on of domestic employment; the yard, garden or field which is near to and used in connection with the dwelling”). “[W]hether a particular place is within the curtilage of the home is determined on a case-by-case basis.” Jefferson, 27 Va.App. at 16, 497 S.E.2d at 481 (citing United States v. Dunn, 480 U.S. 294, 301 n. 4, 107 S.Ct. 1134, 1140 n. 4, 94 L.Ed.2d 326 (1987)). In determining whether the area in question constitutes curtilage, “particular reference” to the following four factors is helpful:
the proximity of the area claimed to be curtilage to the home, [2] whether the area is included within an enclosure surrounding the home, [3] the nature of the uses to which the area is put, and [4] the steps taken by the resident to protect the area from observation by people passing by.
*606Dunn, 480 U.S. at 301, 107 S.Ct. at 1140; Jefferson, 27 Va.App. at 16, 497 S.E.2d at 481. “[TJhese factors are useful analytical tools only to the degree that, in any given case, they bear upon the centrally relevant consideration — -whether the area in question is so intimately tied to the home itself that it should be placed under the home’s ‘umbrella’ of Fourth Amendment protection.” Dunn, 480 U.S. at 301, 107 S.Ct. at 1140.
Applying the Dunn factors to this case, we conclude that the portion of the driveway from which Cox observed the juveniles drinking beer — the area next to the bush — falls within the curtilage of the Robinsons’ home. First, the area next to the bush is within a few feet of the home itself. Second, the Robinsons testified that they used the area for washing cars and unloading groceries, home-related activities that evidence the “nature of the uses to which the area is put.” See id. Third, although the area next to the bush is not “included within an enclosure surrounding the home,” see id., the area is protected from public observation. Specifically, although the Robinsons did not erect a fence or post any no-trespassing signs, the trees and layout of the driveway obscure the area from public view. It is evident, therefore, that the area next to the bush is “protect[ed] ... from observation by people passing by.” Id. Given that three out of the four Dunn factors are satisfied, we are compelled to conclude that the area next to the bush is “intimately tied to the home itself” and, thus, falls within the curtilage of the Robinsons’ home. See Jefferson, 27 Va.App. at 17, 497 S.E.2d at 482 (finding that place of defendant’s arrest constituted curtilage because “the proximity of the place where Officer Harpster arrested appellant was extremely dose to appellant’s house and could not be viewed by pedestrians and drivers passing in front of the house ” (emphasis added)); see also United States v. Jenkins, 124 F.3d 768, 773 (6th Cir.1997) (finding that defendant’s backyard is curtilage because it was “well shielded from the view of people passing by on the only public thoroughfare near defendant’s property”).
*607Accordingly, we conclude that the trial court erred in holding that the area of the driveway next to the bush was not a part of the curtilage of the house. However, in light of our holding that the Robinsons did not have a reasonable expectation of privacy in their driveway, see Part II.B, infra, this error is harmless. See Lavinder v. Commonwealth, 12 Va. App. 1003, 1005, 407 S.E.2d 910, 912 (1991) (en banc) (noting that an error is harmless “if a reviewing court can conclude, without usurping the ... fact finding function, that, had the error not occurred, the [result] would have been the same”).
B. Whether the Robinsons Had A Reasonable Expectation of Privacy in the Area of the Driveway by the Front Sidewalk
Although Cox was positioned within the curtilage when he made his observations, that determination does not end our inquiry. It is well established that “ ‘[w]hat a person knowingly exposes to the public ... is not a subject of Fourth Amendment protection,’ ” California v. Ciraolo, 476 U.S. 207, 213, 106 S.Ct. 1809, 1813, 90 L.Ed.2d 210 (1986) (quoting Katz v. United States, 389 U.S. 347, 351, 88 S.Ct. 507, 511, 19 L.Ed.2d 576 (1967)), because there is no reasonable expectation of privacy in items or places that are open to public observation. See California v. Greenwood, 486 U.S. 35, 41, 108 S.Ct. 1625, 1629, 100 L.Ed.2d 30 (1988). The question we must answer, therefore, is whether the Robinsons knowingly exposed to the public the area of their driveway next to the bush, the place from which Cox viewed the criminal activity.1
*608The Commonwealth argues that the Robinsons knowingly-exposed to the public the area by the front sidewalk because: (1) the Robinsons’ driveway is viewable from the state road, and (2) visitors exercising an implied invitation to the Robin-sons’ home would use that area to access the house and front door. Although we disagree with the former contention, we conclude that, under the circumstances of this case, the Robin-sons impliedly invited members of the public onto their driveway on the night in question. Accordingly, because the Robinsons relinquished any reasonable expectation of privacy in this portion of their driveway, the Fourth Amendment does not apply to that area of the curtilage, and we therefore affirm the trial court’s denial of the motions to suppress.
1. Whether the Driveway is Visible From the Public Road
The Commonwealth argues that the Robinsons have no reasonable expectation of privacy in their driveway because a segment of the driveway is visible from the state road. We disagree with this contention. We note that each of the cases relied upon by the Commonwealth is distinguishable because, in those cases, the driveway was viewable in its entirety from a public thoroughfare. See Shaver v. Commonwealth, 30 Va. App. 789, 793, 797, 520 S.E.2d 393, 395, 397 (1999) (upholding the police search of an ATV parked in defendant’s driveway because the ATV was “visible from the road” and because “defendants made no attempt to restrict or shield the driveway from public view”); see also United States v. Roccio, 981 F.2d 587, 591 (1st Cir.1992) (finding no reasonable expectation of privacy in car and driveway where the car “was clearly visible from the street on an unobstructed driveway”); Maisano v. Welcher, 940 F.2d 499, 503 (9th Cir.1991) (“ ‘The expectation of privacy which a possessor of land may reasonably have while carrying on activities on his driveway will generally depend upon the nature of the activities and the degree of visibility from the street.’” (emphasis added) (quoting United States v. Magana, 512 F.2d 1169, 1171 (9th Cir.1975))); United States v. Smith, 783 F.2d 648, 650 (6th Cir.1986) (finding no reasonable expectation of privacy in defendant’s driveway *609where “there were no obstructions between the [public] road and the house”); United States v. Humphries, 636 F.2d 1172, 1179 (9th Cir.1980) (finding police entry into driveway to view a vehicle license plate violated no reasonable expectation of privacy where “the auto was visible from the street” and where “the driveway was [not] enclosed by a fence, shrubbery or other barrier”); cf. State v. Kelly, 119 S.W.3d 587, 593-94 (Mo.Ct.App.2003) (finding no reasonable expectation of privacy in the area around stairs leading to a front porch because “the area was not enclosed or protected from observation by passersby in any way and was entirely visible from the public street”).
Here, only a portion of the driveway was viewable from the state road, and the area in the driveway from which Cox conducted his observations was shielded from public view by the trees and the bend of the driveway. Indeed, the trial court specifically found that Cox could not see the backyard or the garage due to the trees located between the branches of the driveway, and it is evident that he could not see the two juveniles drinking beer until he reached the area next to the bush, which, as discussed above, was not viewable from the state road. Because the area from which Cox observed the criminal activity was not viewable to members of the public traveling on the state road, the Robinsons legitimately retained a reasonable expectation of privacy in that area of the driveway unless they extended to the public an express or implied invitation to enter the property. See State v. Carter, 54 Or.App. 852, 636 P.2d 460, 462 (1981) (finding that defendant had reasonable expectation of privacy in a portion of his property beyond an inner gate because that area was not viewable from beyond an outer metal gate).
2. Implied Invitation
The Commonwealth also argues that the Robinsons had no reasonable expectation of privacy in the area by the front sidewalk because, on the night of the party, the Robinsons extended an implied invitation to anyone, including a police officer, to approach the front door and knock. The Common*610wealth’s argument is that, in approaching the front door, a visitor would necessarily have to enter and walk up the driveway and then cross the area next to the bush in order to access the walkway to the front door. Because the Robinsons should expect visitors, including a police officer, to enter the same area that Cox entered, the Commonwealth reasons that the Robinsons knowingly exposed that area to the public. The Commonwealth concludes that the Robinsons therefore cannot have a reasonable expectation of privacy in that particular area and, as a result, Cox’s presence in that area did not offend the Fourth Amendment.
Considering the totality of the circumstances of this case, we agree with the Commonwealth and conclude that the Robinsons extended an implied invitation to the public— including law enforcement officers — to use their driveway and front sidewalk when attempting to contact the owners or occupants of the property. We also conclude that, taking, as we must, the historical facts in the light most favorable to the Commonwealth, Cox’s conduct did not fall outside the scope of this implied invitation.
a. Whether the Robinsons Extended an Implied Invitation to Enter the Premises
It is generally recognized that, unless they affirmatively warn or discourage trespassers, owners or possessors of private property implicitly invite the public to intrude upon certain, limited areas of their property. As we have noted,
“People commonly have different expectations, whether considered or not, for the access areas of their premises than they do for more secluded areas. Thus, we do not place things of a private nature on our front porches that we may very well entrust to the seclusion of a backyard, patio or deck. In the course of urban life, we have come to expect various members of the public to enter upon such a driveway, e.g., brush salesmen, newspaper boys, postmen, Girl Scout cookie sellers, distressed motorists, neighbors, friends. Any one of them may be reasonably expected to report observations of criminal activity to the police.”
*611Shaver, 30 Va.App. at 796, 520 S.E.2d at 397 (quoting State v. Corbett, 15 Or.App. 470, 516 P.2d 487, 490 (1973)).
This invitation, where it exists, extends only to those areas of the property that would be used when approaching the residence in an ordinary attempt to speak with the occupants. See id. Thus, areas of the curtilage that must be crossed in order to approach the front door — for example, the driveway, front sidewalk, and front porch — are generally exempted from Fourth Amendment protection. See, e.g., State v. Clark, 124 Idaho 308, 859 P.2d 344, 349 (Ct.App.1993) (“There is an implied invitation for the public to use access routes to the house, such as parking areas, driveways, sidewalks, or pathways to the entry, and there can be no reasonable expectation of privacy as to observations which can be made from such areas.”). As a result, if the property owner has implicitly invited the public to use a particular “path” when attempting to access his home, he has no reasonable expectation of privacy in that area. See id.
By extension, the same implied invitation is given to police officers who enter the curtilage while in pursuit of legitimate police business. See Shaver, 30 Va.App. at 796, 520 S.E.2d at 397 (“ ‘If one has a reasonable expectation that various members of society may enter the property in their personal or business pursuits, he should find it equally likely that the police will do so.’ ” (quoting Corbett, 516 P.2d at 490)); see also State v. Cada, 129 Idaho 224, 923 P.2d 469, 477 (Ct.App.1996) (“[T]he direct access routes to the house, includ ing parking areas, driveways and pathways to the entry, are areas to which the public is impliedly invited, and [] police officers restricting their activity to such areas are permitted the same intrusion and the same level of observation as would be expected from a ‘reasonably respectful citizen.’ ”).2 Accordingly, “[w]hen police enter onto private property in order to conduct an investigation or for another legitimate purpose *612and restrict their entry to places that other visitors would be expected to go, such as walkways, driveways, or porches, any observation made from these areas is permissible under the Fourth Amendment.” Trimble v. State, 816 N.E.2d 83, 88 (Ind.Ct.App.2004); see also State v. Maxfield, 125 Wash.2d 378, 886 P.2d 123, 134 (1994) (“If a law enforcement officer or agent does not go beyond the area of the residence that is impliedly open to the public, such as the driveway, the walkway, or an access route leading to the residence, no privacy interest is invaded.”).
An implied invitation is generally presumed to exist absent evidence of an affirmative intent to exclude the public from the premises. See, e.g., People v. Kozlowski, 69 N.Y.2d 761, 513 N.Y.S.2d 101, 505 N.E.2d 611, 612 (1987) (“Absent evidence of intent to exclude the public, the entryway to a person’s house offers implied permission to approach and knock on the front door.”); State v. Somfleth, 168 Or.App. 414, 8 P.3d 221, 227 (2000) (“A homeowner can abrogate the presumption of implied consent to approach the front door by undertaking sufficient steps to exclude casual visitors from the front yard.”). Here, then, we must consider whether, under the totality of the circumstances, the Robinsons affirmatively intended to exclude members of the public from their premises. See generally State v. Wyatt, 131 Idaho 562, 961 P.2d 653, 656 (Ct.App.1998) (“The determination whether a particular citizen had a legitimate expectation of privacy depends upon the unique facts of each case. We therefore examine the citizen’s efforts to protect his own privacy from observation by the general public, taking into account norms of social conduct and the nature of the premises.”).
Factors that may be particularly relevant to this determination include, inter alia: (1) whether the homeowner has erected any physical barriers, such as gates or fences, across the entrance to the property, and (2) whether the homeowner has posted signs, such as “no trespassing” or “private property” signs, indicating a desire to exclude the public from the premises. See, e.g., State v. Christensen, 131 *613Idaho 143, 953 P.2d 583 (1998) (no implied invitation to enter where the entrance to the driveway was obstructed by a closed gate posted with a “no trespassing” sign); State v. Pacheco, 101 S.W.3d 913, 919 (Mo.Ct.App.2003); State v. McIntyre, 123 Or.App. 436, 860 P.2d 299, 301 (1993) (“[Cjourts must consider all surrounding circumstances, including the existence of a fence, to determine the residents’ intent.”); State v. Ridgway, 57 Wash.App. 915, 790 P.2d 1263, 1265 (1990) (holding that marijuana recovered from doorstep should have been suppressed because police observed the marijuana after walking around a closed gate and evading guard dogs while approaching house).
Here, the Robinsons did not erect any physical barriers barring entry onto their property. There were no gates, fences, wires, or highway cones indicating that members of the public were not welcome to use the Robinsons’ driveway and front sidewalk in an effort to speak with the occupants of the premises. Nor did they post any signs indicating that the general public was not welcome to enter upon their property to approach their front door. Considering the totality of the circumstances, we conclude that the Robinsons extended to the public an implied invitation to enter the driveway and front sidewalk of their premises.
b. Whether Cox Exceeded the Scope of the Implied Invitation
Although we hold that the Robinsons extended an implied invitation to the public to enter their property and approach the front door, we must also consider whether Cox’s conduct on the night of the party exceeded the scope of that implied invitation. Ultimately, whether the officer exceeded the scope of the implied invitation “cannot be determined by a fixed formula,” but must instead “be based on the facts and circumstances of each case.” People v. Thompson, 221 Cal. App.3d 923, 270 Cal.Rptr. 863, 874 (1990).3
*614“[U]nder normal circumstances, uninvited visitors coming to a residence to speak with an owner or resident are expected to come to the residence’s most direct, obvious, and prominent entryway, which in most cases is the front door.” Trimble, 816 N.E.2d at 88. These visitors “are also expected to leave by the same route after knocking on the front door and receiving no response,” unless the “nature of the circumstances surrounding the visit” indicates that the visitor “could reasonably be expected to seek out residents through areas other than the front door.” Id. Generally, “a substantial and unreasonable departure from the normal access route will exceed the scope of the implied invitation and intrude upon a constitutionally protected privacy interest.” Clark, 859 P.2d at 350.
Also, an implied invitation to approach the front door of a private residence is limited in scope to those persons who are on the property for a “legitimate social or business purpose.” State v. Cloutier, 544 A.2d 1277, 1280 (Me.1988). In the context of law enforcement officers, officers who are located on the curtilage for the purpose of approaching the front door and questioning the residents of the house are deemed to be pursuing a “legitimate purpose.” See, e.g., Shaver, 30 Va.App. at 793, 794, 520 S.E.2d at 395, 396 (noting that “investigators intended to speak with the defendants” and that the investigators first “knocked on the front door of the residence but no one answered”).4
*615Although the implied invitation does permit officers to seek out the occupants of a residence in order to “investigate,” the scope of this invitation does not encompass the right to conduct a general search of the premises. See, e.g., United, States v. Bradshaw, 490 F.2d 1097, 1100 (4th Cir.1974) (noting that the officer must have a legitimate purpose other than conducting “a search of such premises directed against the accused”); see also Rogers v. Pendleton, 249 F.3d 279, 288 (4th Cir.2001); Alvarez v. Montgomery County, 147 F.3d 354, 358 (4th Cir.1998). As noted by the Fourth Circuit,
the right to “knock and talk,” that is, to knock on a residence’s door or otherwise approach the residence seeking to speak to the inhabitants, [is] not the right to make a general investigation in the curtilage based on reasonable suspicion. A contrary rule would eviscerate the principle of Oliver and Dunn that the curtilage is entitled to the same level of Fourth Amendment protection as the home itself.
Rogers, 249 F.3d at 289. A police officer exceeds the legitimate scope of an implied invitation if he seeks to “convert[ ] this limited license to do what any citizen may do — approach the house and speak to the inhabitant or owner — into a license to search for ‘evidence.’ ” Id. at 294. Thus, if a law enforcement officer, in an attempt to uncover illicit activity, strays from the “path” that is impliedly open to the public, he has exceeded the scope of the implied invitation and, as a result, violated the Fourth Amendment.
Similarly, entering the property late at night, especially if accompanied by the use of subterfuge, may exceed the scope of the implied invitation. As noted by one court,
Furtive intrusion late at night or in the predawn hours is not conduct that is expected from ordinary visitors. Indeed, if observed by a resident of the premises, it could be a cause for great alarm. As compared to open daytime approaches, surreptitious searches under the cover of darkness create a greater risk of armed response — with potentially tragic results — from fearful residents who may mistake the police officers for criminal intruders.
*616Cada, 923 P.2d at 478; see also Griffin v. State, 347 Ark. 788, 67 S.W.3d 582, 587 (2002) (“ ‘[TJhere is no rule of private or public conduct which makes it illegal per se, or a condemned invasion of the person’s right of privacy, for anyone openly and peaceably, at high noon, to walk up the steps and knock on the front door of any man’s castle with the honest intent of asking questions of the occupant thereof whether the questioner be a pollster, a salesman, or an officer of the law.’” (internal quotations omitted) (emphasis added) (quoting Davis v. United States, 327 F.2d 301, 303 (9th Cir.1964))); Brown v. State, 392 So.2d 280, 284 (Fla.Dist.Ct.App.1980) (finding that police violated defendant’s reasonable expectation of privacy when they entered defendant’s driveway without a warrant at 1:45 a.m. and arrested him); Cloutier, 544 A.2d at 1280 (noting that “the implied invitation extends only to recognized access routes ... and to reasonable times of day ” (emphasis added)); State v. Myers, 117 Wash.2d 332, 815 P.2d 761, 769 (1991) (noting that whether a police officer enters a premises during the daylight hours is relevant in determining whether the scope of an implied invitation to enter premises has been exceeded).
Also, although law enforcement officers who “enter areas of the curtilage which are impliedly open” to the public are “free to keep their eyes open,” State v. Seagull, 95 Wash.2d 898, 632 P.2d 44, 47 (1981), an officer who implements an overly intrusive means of investigation, such as the use of binoculars or other sensory-enhancing devices, may exceed the scope of the implied invitation. See Cada, 923 P.2d at 477 (“The scope of the implied invitation to enter areas of the curtilage that provide direct access to the house ... may be exceeded where officers employ a particularly intrusive method of viewing.”); Cloutier, 544 A.2d at 1280 (holding that the defendant had no reasonable expectation of privacy in a marijuana plant where, inter alia, the officer “detected the contraband by means of his natural senses”). But cf. State v. Lee, 633 P.2d 48, 51 (Utah 1981) (“[T]he use of a flashlight to assist the natural vision at night does not make an ‘observation’ a ‘search.’ ”).
*617Here, considering the totality of the circumstances, we conclude that Cox did not exceed the scope of the implied invitation to enter the premises and approach the front door of the Robinsons’ home. Cox entered the driveway, began to drive toward the residence, and, before he reached the area of the driveway where the front walk intersects with the driveway, he saw the minors drinking in the Robinsons’ backyard. At that point, Cox had gone no further than any member of the public would have gone in an attempt to contact the owners of the property. He did not stray from the “path” leading directly from the road to the front door (i.e., the driveway and the front sidewalk), nor did he attempt to conduct a general search of the premises through use of an overly intrusive means of investigation.
Also, although Cox entered the curtilage of the Robin-sons’ home at 11:00 p.m., a late hour of the evening, this entry did not necessarily exceed the scope of the implied invitation. “Under some circumstances, the mere fact that the intrusion was made late at night may be a factor suggesting that the police conduct was unduly intrusive.” State v. Morris, 131 Idaho 562, 961 P.2d 653, 657 n. 3 (Ct.App.1998). Here, however, the lights along the Robinsons’ front sidewalk and the lights on the front porch were still turned on. Also, multiple cars were parked along the driveway and on the public road in front of the house. These factors give rise to a reasonable inference that the implied invitation to approach the front door of the residence had not yet been rescinded for the night.5 Also, we note that Cox drove up the driveway with his headlights turned on — the same way that any member of the general public would presumably have approached the house — rather than using subterfuge or the “cover of darkness” in an attempt to disguise his approach. Compare Cada, 923 P.2d at 478 (officers exceeded scope of implied invitation where they engaged in a “clandestine intrusion ... under *618cover of darkness in the dead of night”), with Clark, 859 P.2d at 346 (officers did not exceed scope of implied invitation where the officers went to the fi-ont door of the residence at 10:00 p.m. to investigate a neighbor’s complaint about a loud party).6 Considering the totality of the circumstances, we conclude that, on the night in question, the implied invitation to enter the Robinsons’ premises was still open even at this late hour, and Cox did not exceed the scope of this implied invitation when he drove up the Robinsons’ driveway.
Moreover, Cox entered the curtilage of the Robin-sons’ home with the purpose of investigating reports of underage drinking at the residence. “[T]he investigation of an anonymous tip is clearly legitimate police activity so long as the investigation does not violate applicable constitutional provisions.” Divello v. State, 782 N.E.2d 433, 437-38 (Ind.Ct. App.2003). Because Cox entered the premises to “investigate,” he had a legitimate purpose for being present on the Robinsons’ driveway at the time he viewed the illicit activity.
Also, we do not accept the Robinsons’ argument that Cox’s subjective intent indicates that the entry exceeded the scope of the implied invitation. Generally, the determination of whether a Fourth Amendment violation has occurred is based on “ ‘an objective assessment of the officer’s actions ... and not on the officer’s state of mind at the time the challenged action was taken.’ ” Limonja v. Commonwealth, 8 Va.App. 532, 538, 383 S.E.2d 476, 480 (1989) (en banc) (quoting Maryland v. Macon, 472 U.S. 463, 470-71, 105 S.Ct. 2778, 2782-83, 86 L.Ed.2d 370 (1985)). Although cases from other jurisdictions have inquired into the officer’s subjective intent, we note that, in each of those cases, the officer’s intent only *619became relevant if the officer exceeded the ordinary scope of the implied invitation by, for example, invading other areas of the curtilage after attempting a “knock and talk.” See, e.g., Estate of Smith v. Marasco, 318 F.3d 497, 520-21 (3d. Cir. 2003) (remanding qualified immunity case for further factual determinations where the officers knocked on the front door, the defendant failed to answer, and the officers then entered the backyard of the residence); Alvarez, 147 F.3d at 357 (inquiring into officer’s subjective purpose for entering the backyard where the officers, who were investigating an underage drinking party, approached the front door, noticed a sign that said “Party in Back,” and then went to the backyard to “speak with the party’s host”).
Without expressly adopting or rejecting the rationale of these cases, we note that they are distinguishable because, here, Cox had not yet performed a “knock and talk,” nor had he invaded any area of the curtilage beyond the “path” to the front door. Rather, when Cox viewed the illicit activity, he had not yet finished driving up the driveway. Under the circumstances of this case, then, there is no additional intrusion into the curtilage that would necessitate an inquiry into Cox’s subjective intent. Cf. McIntyre, 860 P.2d at 302 (holding that “[t]he trial court’s reliance on the officers’ investigative purpose was misplaced” because “ ‘[cjriminal investigation is as legitimate a societal purpose as is census taking or mail delivery’ ” (quoting Corbett, 516 P.2d at 490) (second alteration in original)).
Considering the totality of the circumstances, we therefore conclude that the Robinsons extended an implied invitation to the public to enter their driveway on the night of the party. We further conclude that, when Cox entered the curtilage with the purpose of “investigating” the allegations of underage drinking, he did not exceed the scope of this implied invitation because, at the point in time when he viewed the illicit activity, he had gone no further than an ordinary member of the public would have gone in an attempt to contact the occupants of the property. Accordingly, because the Robinsons extended an implied invitation to enter the property, and because Cox did *620not exceed the scope of that invitation, the Robinsons had no reasonable expectation of privacy in the area of the driveway by the bush, and Cox’s actions neither implicated nor violated the Fourth Amendment.
C. Because the Fourth Amendment Does Not Apply, The Evidence Is Admissible
The Robinsons submit that the trial court erred in its legal conclusion that Cox’s observations were admissible pursuant to the plain view exception to the warrant requirement.7 However, we need not reach the issue of whether the plain view exception applies because Cox’s presence in the Robinsons’ driveway did not implicate the Fourth Amendment. Rather, because the illicit conduct was clearly visible from an area in which the Robinsons had no reasonable expectation of privacy, the plain view doctrine applies, and the observations are admissible.
That is, because the Robinsons had extended an implied invitation to the public to use the driveway to access the front door of their home, they had no reasonable expectation of privacy in that area. See Clark, 859 P.2d at 349 (“There is an implied invitation for the public to use access routes to the house ... and there can be no reasonable expectation of privacy as to observations which can be made from such areas.”); Divello, 782 N.E.2d at 437 (“[A]n individual does not have a reasonable expectation of privacy with regard to things or activities within a residence that may be observed by persons using their natural senses from places impliedly open to a visitor’s entry.”). And, because the Robinsons had no reasonable expectation of privacy in the illicit activities that were clearly visible from their driveway, the Fourth Amend*621ment does not apply to any observations made by a police officer who was present in the driveway and complying with the terms of that implied invitation. See Illinois v. Andreas, 463 U.S. 765, 771, 103 S.Ct. 3319, 3324, 77 L.Ed.2d 1003 (1983) (“If the inspection by police does not intrude upon a legitimate expectation of privacy, there is no ‘search’ subject to the Warrant Clause.”); see also Clark, 859 P.2d at 348 (“[A] policeman’s mere observation from a vantage point that does not infringe upon a privacy interest, of something open to public view, normally implicates no Fourth Amendment constraints because observation of items readily visible to the public is not a ‘search.’ ”); State v. Harris, 919 S.W.2d 619, 624 (Tenn.Crim.App.1995) (“What an officer sees from a vantage point along the walkway between the public road and the front door is not protected by [] the Fourth Amendment. ...”). Because the Fourth Amendment does not apply, no warrant is required and, therefore, no exception to the warrant requirement is needed. See generally Commonwealth v. Carelli, 377 Pa.Super. 117, 546 A.2d 1185 (1988) (“Because there is no search, there is no need for an exception to permit admission of testimony relating to the observation.” (emphasis in original)). Because Cox’s observations do not implicate the Fourth Amendment, those observations are admissible in their entirety.
III. CONCLUSION
We hold that, under the facts of this case, the area of the driveway next to the bush is part of the curtilage of the Robinsons’ home. We further hold, however, that the area was not protected by the Fourth Amendment because the Robinsons had no reasonable expectation of privacy in that area of the curtilage. Rather, because the Robinsons extended an implied invitation to members of the public to enter the portion of driveway before the walkway to the front door, Cox’s presence on the driveway did not implicate the Fourth Amendment and, therefore, did not constitute an illegal search. Because Cox’s observations did not implicate the Fourth Amendment, the trial court properly denied the Robin-*622sons’ motions to suppress. Accordingly, we affirm the convictions.
Affirmed.
. We agree with the Commonwealth that observation of the curtilage is not prohibited when the police conduct observations from a public vantage point. See generally Florida v. Riley, 488 U.S. 445, 109 S.Ct. 693, 102 L.Ed.2d 835 (1989) (approving observation of the curtilage from a helicopter); Ciraolo, 476 U.S. 207, 106 S.Ct. 1809, 90 L.Ed.2d 210 (approving observation of the curtilage from an airplane); Jenkins, 124 F.3d 768 (approving observation of the curtilage from a helicopter). Here, however, the police did not observe the curtilage from a public vantage point, such as public airspace or a public roadway; rather, the police entered the curtilage and from that private vantage point observed criminal activity.
. See generally 1 Wayne R. LaFave, Search and Seizure § 2.3(f), at 600-03 (4th ed.2004).
. Relevant factors that have been identified include "whether the officer (1) spied into the house; (2) acted secretly; (3) approached the house in *614daylight; (4) used the normal, most direct route to the house; (5) attempted to talk with the resident; (6) created an artificial vantage point; and (7) made the discovery accidentally.” State v. Ross, 91 Wash.App. 814, 959 P.2d 1188, 1190 (Ct.App.1998).
. See also United States v. Hammett, 236 F.3d 1054, 1059 (9th Cir.2001) (“Law enforcement officers may encroach upon the curtilage of a home for the purpose of asking questions of the occupants."); United States v. James, 40 F.3d 850, 862 (7th Cir.1994) (finding that police did not violate the Fourth Amendment where they used a walkway, which was part of the curtilage of the home, "[i]n their attempt to reach the lower floor residents”); United States v. Daoust, 916 F.2d 757, 758 (1st Cir.1990) (noting that a "policeman may lawfully go to a person's home to interview him”).
. See also Morris, 961 P.2d at 657 n. 3 (noting that the "late hour” was "not such a factor in this case,” reasoning that "[i]f the investigation had been delayed until the next day, the [subject of the investigation] might have been gone”); Ross, 959 P.2d at 1191 (finding that the officers exceeded the scope of an implied invitation where "the officers arrived in an unmarked car, in plain clothes, after midnight, and made no attempt to contact [the defendant] or otherwise notify him of their presence”).
. In order for a search to come within the plain view exception, two requirements must be met: "(a) the officer must be lawfully in a position to view and seize the item, [and] (b) it must be immediately apparent to the officer that the item is evidence of a crime, contraband, or otherwise subject to seizure.” Hamlin v. Commonwealth, 33 Va.App. 494, 502, 534 S.E.2d 363, 367 (2000) (citations omitted), aff'd on reh’g en banc, 35 Va.App. 375, 545 S.E.2d 556 (2001).