Environmental Protection Agency Overflights

and Fourth Amendment Searches

R outine overflights o f industrial plants by the E nvironm ental P rotection A g en cy (E P A ), 

conducted at law ful altitudes and em ploying com m ercially available visual aids, d o not 

constitute searches u nder th e F o u rth A m endm ent.

C onsidering the co m prehensive n atu re o f the federal environm ental regulatory schem e, 

co rp o ra te businesses m ay hav e no legitim ate expectation o f privacy against E P A 

observations for th e purpose o f d etectin g em issions into the air o r discharges into 

w ater.

September 23, 1980

MEMORANDUM OPINION FOR 

TH E DEPUTY ATTORNEY GENERAL

This responds to your request for our views on the question whether 

the Environmental Protection Agency’s (EPA’s) routine overflights of 

possible sources of pollution constitute searches under the Fourth 

Amendment. This question is addressed in a draft memorandum prepared by the EPA and submitted to the Land and Natural Resources 

Division of the Department of Justice. The EPA memorandum states 

that routine overflights of possible sources of unlawful pollution are an 

important part of its overall enforcement program. Aerial observations 

are used to detect discharges into water, emissions into the air (especially at night), and hazardous waste disposal sites among other things. 

Flights are typically made at altitudes meeting FAA regulations, and 

observations are made with equipment that includes infrared cameras 

(to detect heat differentials caused by underground discharges into 

water) and an instrument called the “Enviro-Pod,” which is essentially 

equivalent to a high-quality single lens reflex 35mm camera with good 

lenses. Such cameras, as well as the thermal infrared scanner, are 

commercially available.

The EPA memorandum concludes that the overflights do not constitute searches as long as they occur at lawful and reasonable altitudes 

and use equipment no more sophisticated than commercially available 

equipment and as long as the observed facility has not taken measures

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to shield itself from overhead observation.1 For the reasons that follow, 

our analysis agrees that the EPA memorandum is substantially correct.

I.

The governing standard for whether an observation constitutes a 

search under the Fourth Amendment was established in Katz v. United

States, 389 U.S. 347 (1967), in which the Supreme Court rejected the 

requirement that a physical intrusion occur before a search could be 

found and held that attaching an electronic listening device to the 

outside of a public telephone booth constituted a search.

What a person knowingly exposes to the public, even in 

his own home or office, is not a subject of Fourth 

Amendment protection. . . . But what he seeks to preserve as private, even in an area accessible to the public, 

may be constitutionally protected.

Id. at 351-52. A governmental observation of an individual constitutes a 

search whenever it “violate[s] the privacy upon which he justifiably 

relie[s].” Id. at 353. As explained by Justice Harlan, this rule contains 

“a twofold requirement, first that a person have exhibited an actual 

(subjective) expectation of privacy and, second, that the expectation be 

one that society is prepared to recognize as ‘reasonable.’” Id. at 361 

(Harlan, J., concurring).

In United States v. Chadwick, 433 U.S. 1 (1977), the Supreme Court 

characterized the Fourth Amendment as protecting people “from unreasonable government intrusions into their legitimate expectations of 

privacy.” Id. at 7. In Rakas v. Illinois, 439 U.S. 128 (1978), the Court 

read Katz as holding that

capacity to claim the protection of the Fourth Amendment depends not upon a property right in the invaded 

place but upon whether the person who claims the protection of the Amendment has a legitimate expectation of 

privacy in the invaded place.

Id. at 143. The Court explained in a footnote that

a “legitimate” expectation of privacy by definition means 

more than a subjective expectation of not being discovered. . . . Legitimation of expectations of privacy by law 

must have a source outside of the Fourth Amendment, 

either by reference to concepts of real or personal prop1 A memorandum from (he D rug Enforcem ent Administration (D E A ) coneurs in these conclusions. 

The D E A memorandum actually goes farther than the EPA in its conclusions, cursorily arguing that 

even attem pts to shield objects or activity from aerial view would not create a reasonable expectation 

o f privacy that would make aerial observation o f those objects o r activities that w ere in fact 

unconcealed a search for Fourth Amendm ent purposes.

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erty law or to understandings that are recognized and 

permitted by society.

Id. at 143-44 n.12. Because flights at lawful altitudes do not invade a 

landowner’s property (see United States v. Causby, 328 U.S. 256 (1946);

49 U.S.C. §1508 (1976)), the inquiry regarding EPA overflights is 

whether societal understandings recognize a legitimate expectation of 

privacy against aerial viewing of a commercial facility for the purpose 

of detecting unlawful pollution.

H.

As both the EPA memorandum, and the DEA memorandum mentioned in note 2 supra, point out, there are no federal cases on the 

question of whether an aerial observation can constitute a search for 

Fourth Amendment purposes. Two Supreme Court decisions, however, 

are especially relevant to the EPA overflight search question.

In G.M. Leasing Corp. v. United States, 429 U.S. 338 (1977), the 

Supreme Court unanimously held that corporations are protected by 

the Fourth Amendment. (The Court had farlier held that Fourth 

Amendment guarantees apply to businesses as possible subjects of regulatory searches. Camara v. Municipal Court, 387 U.S. 523 (1967); See v. 

City o f Seattle, 387 U.S. 541 (1967).) The decision recognized that “a 

business, by its special nature and voluntary existence, may open itself 

to intrusions that would not be permissible in a purely private context.” 

429 U.S. at 353. The Court has yet to elaborate the contours of 

corporations’ reduced protection.2

Because the governmental action challenged in G.M. Leasing was a 

physical entry, the Court did not address the question of what constitutes a search. Rather, it held that the intrusions, acknowledged to be 

searches for constitutional purposes, were not reasonable, distinguishing 

United States v. Biswell, 406 U.S. 311 (1972) (warrantless search of 

locked storeroom of a federally licensed gun seller, pursuant to inspection procedure authorized by Gun Control Act of 1968, held constitutional). The Court decided that where the intrusion was undertaken to 

enforce the tax laws against the corporation and “was not based on the 

nature of its business, its license, or any regulation of its activities,” the 

corporation had Fourth Amendment rights identical to those of an 

individual. 429 U.S. at 354. In accordance with Marshall v. Barlow's,

436 U.S. 307 (1978) and Biswell, supra, these elements may serve to 

justify warrantless EPA overflights as reasonable, given the specific

2 T he EPA memorandum refers to Clinton Community Hospital Corp. v. Southern Maryland Medical

Center. 374 F. Supp. 450, 456 (D. Md. 1974), in which (he court asserted that corporations have no 

right to privacy under the Fourth Amendment. As the mem orandum points out, the court relied on 

United States v. Morton Salt C a. 338 U.S. 632 (1950); but that case was decided long before the 

Supreme C ourt first expressly rejected (in G.M. Leasing) the position that corporations have no Fourth 

Amendm ent privacy protection.

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enforcement needs in environmental regulation, even if they are held to 

constitute searches.3 More important for the question whether the 

flights are searches, these elements may be looked to in defining the 

legitimate expectations of privacy of the corporation’s activities. Considered in the context of the detailed environmental regulatory scheme, 

corporate businesses—especially those operating industrial facilities— 

may have no legitimate expectation of privacy against EPA observations for the purpose of detecting emissions into the air or discharges 

into water. It might easily be found that emissions into the air and 

discharges into water visible from public locales are “knowingly 

expose[d] to the public.” Katz, 389 U.S. at 351.

In Air Pollution Variance Board v. Western Alfalfa Corp., 416 U.S. 861 

(1974), the second Supreme Court case of special relevance to the EPA 

overflight search question—decided before G.M. Leasing—the Supreme 

Court unanimously held that the respondent corporation had not been 

the subject of a search when, in daylight, a state health department 

inspector entered the outdoor premises of the corporation’s plant and 

observed the plant’s smoke stacks in order to check for pollution. 

Having neither entered the plant or offices, nor inspected the stacks, 

the official “had sighted what anyone in the city who was near the 

plant could see in the sky—plumes of smoke.” Id. at 865. The Court 

reaffirmed the rule of Hester v. United States, 265 U.S. 57 (1924), that 

Fourth Amendment rights do not extend to “sights seen in ‘the open 

field.’ ” Because the public could enter the premises on which the 

inspector stood, the observation fell within the “open fields” exception 

to the Fourth Amendment.

This case is significant because it unanimously held there to be no 

search when (1) from an “open field,” which the public could routinely 

enter, officials observed (2) publicly visible emissions from (3) a corporation’s plant (4) in order to detect pollution. If aerial observation from 

lawful altitudes is constitutionally equivalent to observation from the 

open fields—and the Court’s emphasis on the observer’s distance from 

the plant, on the fact that the public was not excluded from the 

observer’s position, and on the analogy to taking noise readings while 

standing on a railroad right-of-way suggests that it is—then EPA 

overflights would be exempt from Fourth Amendment requirements 

under the open fields exception.-4 This case presents a strong precedent, 

which any corporation arguing that overflights of its plants are searches 

would have to overcome.5 Nevertheless, each case must be considered

3 This memorandum does not consider the issue w hether a warrantless overflight, if held to be a 

search, would be constitutional.

4 Lower court precedent suggests that the use o f viewing equipment that is not o f extreme 

technological sophistication would not change this conclusion. See discussion infra.

9 It is w orth noting that the United States, as amicus curiae in the case, submitted a brief that 

presented exactly the argum ents that the decision advances. It is also w orth noting that on remand, the 

C olorado courts held that due process did not require notice prior to inspection but did require notice

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on all its facts to determine whether in the particular circumstances, a 

legitimate expectation of privacy has been invaded.6

III.

Because whether a legitimate expectation of privacy has been invaded depends on the full set of circumstances, it is useful to describe 

the several state court aerial observation decisions before attempting to 

catalogue the relevant factors for answering the Fourth Amendment 

question. Generalization is especially difficult with these cases.

In People v. Sneed, 32 Cal. App. 3d 535, 108 Cal. Rptr. 146 (Ct. App. 

1973), a police helicopter hovered at 20-25 feet over defendant’s corral 

near the back of his house on his ranch. Several marijuana plants 

growing in the corral were spotted; though they were hidden from 

public view, they may have been visible from the neighbor’s farm. The 

court found there to be a search, saying that in considering the totality 

of circumstances, it must look to the location of the premises (urban or 

isolated), the natural or artificial barriers to public observation, the 

location of public walkways or roads, and the type of governmental 

authority. Relying on the rule of Harris v. United States, 390 U.S. 234, 

236 (1968), that a non-search observation requires the officials lawfully 

to be at their vantage point, the court noted that the helicopter altitude 

was unlawful and that there was no evidence of regular flights (by 

police, by cropdusters, by mosquito-abatement officials, for example) 

over defendant’s ranch. Defendant’s privacy had therefore been invaded.

In Dean v. Superior Court, 35 Cal. App. 3d 112, 10 Cal. Rptr. 585 

(Ct. App. 1973), defendant had cultivated marijuana on a 3/4-acre plot 

protected from public view by the surrounding hills and forest. Using 

binoculars, police flew as low as 300 feet over the plot. The court 

found that no search had occurred. It reasoned that altitude is a minor 

factor in determining legitimate expectations of privacy; instead, one 

must look to “mankind’s common habits in the use of domestic and 

business property.” 35 Cal. App. 3d at 117. Here, any expectation of 

privacy was “not consistent with the common habits of mankind in the 

use of agricultural and woodland areas.” Id. at 118.

In People v. Superior Court, 37 Cal. App. 3d 836, 112 Cal. Rptr. 764 

(Ct. App. 1974), police, while conducting a routine air patrol at approximately 500 feet above ground, and first using the naked eye, then

very soon afterw ard, al least w hen the inspections w ere to be used in a hearing before the Air 

Pollution V ariance Board. Air Pollution Variance Board v. Western Alfalfa Corp., 553 P.2d 811 (Colo. S. 

Ct. 1976).

6 Though the Air Pollution Variance Board opinion does not cite Katz, the issues presented in the 

tw o cases w ere the same, namely, an observation constituted a search for Fourth Amendment 

purposes. Because the C ourt has read this question as an inquiry into legitimate expectations of 

privacy, the open Helds doctrine should be understood as holding that there are no legitimate 

expectations o f privacy against viewing from an open field, or indeed, from anyw here the observer has 

a right to be.

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20-power gyrostabilized binoculars, spotted large, “conspicuous and 

readily identifiable” automobile parts in the backyard of a residence. 37 

Cal. App. 3d at 839. In these circumstances, no search had occurred.

In Plunkett v. City o f Lakewood, 2 Civ. 49610 (unreported decision 

filed 15 November 1977, Cal. Ct. App., 2d Dist.) cert, denied, 436 U.S. 

945 (1978), city officials’ helicopter overflight of plaintiff’s property, 

and taking of photographs from that vantage point, was held not to 

constitute a search. The available reports of the facts reveal no further 

details.

In State v. Stachler, 570 P.2d 1323 (Haw. S. Ct. 1977), no search was 

found where police flew over defendant’s woods-surrounded marijuana 

during routine helicopter surveillance and using binoculars from about 

300 feet, spotted the marijuana growing in the open field. The court 

relied on the open field exception approved in Air Pollution Variance

Board, noting that the police were flying at a lawful and reasonable 

altitude. The court observed, however, that a violation of legitimate 

expectations of privacy might be found if the overflight were unreasonably or unlawfully low, or if surveillance were intensive or amounted 

to harassment, or if “highly sophisticated viewing devices” were employed. Id. at 1328. Here, occasional overflights by cropdusters, commercial planes, and helicopters made any expectation of privacy in the 

open field unreasonable.

In State v. Brighter, 589 P.2d 527 (Haw. S. Ct. 1979), helicopter 

observation from 200-250 feet resulting in the spotting of a stolen 

automobile van was held not to constitute a search. The court said: 

“No reasonable expectation of privacy can be asserted with respect to 

an object or activity which is open and visible to the public when the 

presence of members of the public may reasonably be anticipated.” Id.

at 530.

In Burkholder v. Superior Court, 96 Cal. App. 3d 421, 158 Cal. Rptr. 

86 (Ct. App. 1979), police, flying in a plane at 1500-2000 feet and using 

7 X 50mm binoculars and a camera with a 135mm telephoto lens, 

discovered a marijuana patch fairly well-hidden in the woods. Relying 

on the Dean agricultural-use test, and distinguishing Sneed on the 

ground that that case involved a “purposeful and intensive (helicopter) 

overflight at an unreasonable and unlawful altitude (20 feet) during a 

random search for contraband” (96 Cal. App. 3d at 426), the court held 

that no search had occurred. The optical aids were permissible, said the 

court, because the patch could be seen without the aids, albeit in less 

detail.

Finally, in People v. Lashmett, 389 N.E.2d 888 (111. App. Ct. 1979), 

police, acting on a tip, flew at 2400 feet over defendant’s farm and 

spotted allegedly stolen large farm equipment. In this first Illinois overflight case, the court found that no search had occurred.

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IV.

The cases suggest that in determining whether a legitimate expectation of privacy has been invaded by aerial observation, a court would 

look to several factors: the altitude of the observer, the type of location 

viewed, the nature of the objects or activities observed, the extent to 

which the area observed was concealed, the equipment used for observation, and the frequency of flights over the observed area. In no case 

is a finding as to any one of these elements conclusive, although an 

extension of the open fields exception to the public airways would 

render altitude a conclusive test.

Altitude. Only the Sneed case, in which the helicopter hovered directly over the observed property at 20-25 feet and caused a very noisy 

disturbance, held an aerial observation to be a search. The other cases 

reached the opposite conclusion; in all of them, the flights were at 

lawful and reasonable altitudes ranging from 200-2400 feet. EPA 

overflights occur at lawful altitudes, but altitude is not determinative of 

the reasonableness of privacy expectations. Dean; Stachler.

In our view, because of the difficulty of protecting against aerial 

observation, it is unlikely that a court would adopt the general rule that 

observations from public airspace, like those from a public road, fall 

within the open field exception. Without such a blanket exception, the 

other elements noted by courts will continue to inform decisions about 

the legitimacy of privacy expectations.

Type o f Location. The relevance of the type of location viewed was 

explained by a federal court in a case involving FBI agents peering 

through a gap in boards covering a garage window facing a public 

alley. In United States v. Vilhotti, 323 F. Supp. 425 (S.D.N.Y. 1971), the 

court said:

[A]n agent is permitted the same license to intrude as a 

reasonably respectful citizen would take. Therefore, the 

nature of the premises inspected—e.g., whether residential, 

commercial, inhabited, or abandoned—is decisive; it determines the extent- of social inhibition on natural curiosity 

and, inversely, the degree of care required to insure 

privacy.

Id. at 431. Although “decisive” is in our opinion too strong a characterization, the nature of the premises is critical to the legitimacy of 

privacy expectations. A residence or its backyard (Sneed) is socially 

understood to give greater protection against outside intrusion than is a 

farm or business (Dean; Lashmett). Looking into a building is far more 

likely to be held a search than is observing objects or activities on the 

outside. See United States v. Kim, 415 F. Supp. 1252 (D. Haw. 1976) 

(telescope looking into apartment a search; observing balcony may not 

be search). As indicated by the Supreme Court in G.M. Leasing, busi790
nesses receive less protection from the Fourth Amendment than do 

private residences. An industrial facility whose exterior is viewed from 

overhead by the EPA can claim little legitimate expectation of privacy 

consistent with “mankind’s common habits in the use of . . . business 

property.” Dean, 35 Cal. App. 3d at 117.

Nature o f Objects or Activities Observed. Although the nature of the 

premises is an important measure of the extent of social inhibition on 

public curiosity, the kind of objects or activities being observed also 

determines in part the legitimacy of privacy expectations. In particular, 

if the objects or activities are large or conspicuous, any expectation of 

privacy with respect to those objects or activities is less reasonable. 

People v. Superior Court; Lashmett. Because material discharged into 

water or emitted into the air is publicly visible, an expectation of 

privacy with respect to these discharges and emissions would be of 

doubtful legitimacy.

Concealment. The extent to which the observed area is concealed, 

either by natural barriers such as hills, woods, grass, or crops or by 

artificial barriers such as a fence, is an important factor in determining 

the reasonableness of any expectations of privacy. Under the Katz

principle that observation of what a person knowingly exposes to the 

public does not constitute a search, leaving objects or activities visible 

to public walkways (Sneed) or to public roads (Stachler) or to any place 

where “the presence of members of the public. may reasonably be 

anticipated” (Brighter, 589 P.2d at 530) evidences an absence of reasonable expectations of privacy. Conversely, efforts to conceal make expectations of privacy more reasonable. See State v. Kender, 588 P.2d 

447 (S. Ct. Haw. 1979) (small marijuana plants hidden among tall grass 

in yard surrounded by fence; observation from top of fence using 

telescope constitutes search).

What remains unclear is whether expectations of privacy are reasonable when efforts to conceal extend only to landbound observers, not to 

overflights. The list of considerations advanced by the Sneed court is 

directed far more at concealment from landbound observers; moreover, 

the Dean court said that the horizontal extension of an activity is a 

better measure of its privacy protection than is the altitude of the 

overhead plane. None of the cases involve efforts to conceal from 

overhead observation. The EPA memorandum and the DEA memorandum regard concealment from land observation as insufficient to create 

a reasonable expectation of privacy against overhead inspection. 

LaFave, by contrast, argues that such concealment should be sufficient.

1 LaFave, Search and Seizure § 2.3, at 328-30 (1978). The holdings of 

the cases summarized above, however, lead us to the conclusion that 

the significance of efforts to conceal from landbound observers depends 

on the nature of the premises, the type of objects or activities observed, 

and the other factors discussed here. We conclude that an industrial

791
facility should have little expectation of privacy from overhead observation of the exterior of its plant or of the land surrounding it, even if a 

fence surrounds the facility to keep intruders out. By contrast, surrounding the backyard of a residence with a fence should be sufficient 

to raise legitimate expectations of privacy against prying overhead 

observation (i.e., from low altitudes). This judgment rests,.as the cases 

direct, on the general social understanding about the nature of the 

objects or activities that can reasonably be expected to be shielded 

when located on particular kinds of premises. Concealment must therefore be considered only one of the factors relevant to determining the 

legitimacy of expectations of privacy.

Observation Equipment. The use of some visual aids does not automatically transform into a search what would otherwise not be a 

search. For example, binoculars were approved in Burkholder, Dean,

People v. Superior Court, and Stachler. Moreover, use of a camera does 

not transform a non-search into a search. See, e.g., Plunkett, Burkholder,

United States v. McMillon, 350 F. Supp. 593 (D.D.C. 1972). Burkholder

even approved the use of a telephoto lens on the camera. In addition, 

Stachler warned that a search might be held to have occurred if technologically sophisticated equipment were used. It is our conclusion that 

no reasonable expectations of privacy are defeated by the use of commercially available visual aids that do no more that provide greater 

detail than the naked eye can make out on unconcealed objects or 

activities.7

In addition, if an observation would not constitute a search if carried 

out in daylight, using artificial illumination to observe in the dark 

would not render it a search. See United States v. Lee, 274 U.S. 559 

(1927) (use of searchlight to observe boat at night not a search), cited in 

Katz v. United States, supra (supporting proposition that what a person 

knowingly exposes to the public gains no Fourth Amendment protection). If darkness does not generate a legitimate expectation of privacy 

against artificial illumination, it should not shield objects or activities 

against observation with the aid of “see-in-the-dark” equipment. See

Commonwealth v. Williams, 396 A.2d 1286 (Pa. Super. Ct. 1978) (use of 

see-in-the-dark “startron” does not constitute search). Therefore, nighttime overhead observation of the unconcealed exterior of suspected 

sources of pollution, using infrared equipment to detect emitted heat or 

otherwise to observe without illumination, or using binoculars and

7 On facts similar to those in United States v. Kim, supra, a federal court recently found a search in 

the use o f a “high-powered telescope (i.e., a M onolux #4352 telescope with a 22mm viewer)*' to 

observe the inside o f an apartm ent. United States v. Taborda, 491 F. Supp. 50, 51 (E.D.N.Y.). Both 

cases involve an invasion of residential privacy, though some language in Taborda suggests that the 

court envisions a general rule that use o f visual aids constitutes a search. In light o f such cases as 

United States v. Grimes, 426 F.2d 706 (5th Cir. 1970) (binoculared observation of street activity not a 

search), this reading of Taborda would be too broad.

792
cameras with commercially available lenses, should not constitute a 

search.

The use of infrared equipment to detect underground discharges— 

which might be considered concealed from ordinary public observation—is more questionable. Use of magnetometers, x-rays, radiographic 

scanners, or scintillators to perceive concealed objects constitutes a 

search. See, e.g., United States v. Epperson, 454 F.2d 769 (4th Cir. 1972) 

(magnetometer use is search). Nevertheless, the decisions on this aspect 

of search law—indeed all the federal decisions relevant to the significance of visual aids—all concern the invasion of bodily privacy (as 

with the magnetometer at airports) or residential privacy (Kim;

Kender). It is therefore difficult to predict the extent of privacy protection that surrounds underground discharges.

Visual aids have generally been approved as sense-enhancement devices; when an instrument is used to detect what to the observer’s 

senses is undetectable, a search is likely to have occurred. See United

States v. Bronstein, 521 F.2d 459, 465 (2d Cir. 1975) (Mansfield, J., 

concurring). The technology used by the EPA in its searches should be 

evaluated in light of this standard, but it is only one factor in determining the range of legitimate privacy expectations, which are defined as 

well by the nature of the premises, of the objects being observed, and 

the like. In this context, we conclude, detection of heat differentials in 

unconcealed pools of water should violate no legitimate expectations of 

privacy. Indeed, it is likely that, faced with the issue, courts would 

recognize the scientific sophistication of industrial businesses and decline to draw a line between use of the human senses and use of devices 

able to perceive signals other than light, sound, etc., within the human 

range. This would represent a sensible extension of the approval of seein-the-dark devices. As briefly described in the EPA memorandum, 

therefore, use of the overflight detection equipment, in observing those 

facilities technologically sophisticated enough to understand what signals (e.g., light, heat) are being emitted for possible perception, should 

not constitute a search.

Frequency of Overhead Flights. Not surprisingly, the legitimacy of 

expectations of privacy against overhead flights depends on the frequency of such flights. See Sneed, People v. Superior Court, Stachler,

Burkholder. Routine flyovers by commercial aircraft or by police planes 

or helicopters render unreasonable any expectations of privacy with 

respect to objects or activities left open for viewing by these potential 

observers. Thus, the more routine the EPA flights, and the greater the 

air traffic above any observed plant, the less likely is the finding of a 

search.

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V.

Under the Katz test, all the circumstances of an observation must be 

considered before deciding whether it constitutes a search. It is our 

conclusion that routine EPA overflights of industrial plants, conducted 

at lawful altitudes and employing commercially available visual aids to 

detect unconcealed discharges into water or air by observing the exteriors of buildings and open lands, do not constitute searches under the 

Fourth Amendment. In these circumstances, the state court decisions, 

the few relevant federal court decisions, and especially Air Pollution

Variance Board indicate that expectations of privacy are not reasonable. 

Varying any of these circumstances, as the analysis above suggests, 

might require a different result.

L a r r y A . H a m m o n d

Deputy Assistant Attorney General

Office o f Legal Counsel

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