Later Congress passed the Omnibus Crime Control and Safe Streets Act of 1968, and Colorado has passed legislation regarding eavesdropping and wiretapping.

        Hoffa v. United States, 385 U.S. 293 (1966), which was left undisturbed by Katz, held that however strongly a defendant may trust an apparent colleague, his expectations in this respect are not protected by the Fourth Amendment when it turns out that the colleague is a government agent regularly communicating with the authorities.  United States v. White, 401 U.S. 745, 91 S.Ct. 1122, 28 L.Ed.2d 453 (1971)

        Statements made by juvenile not protected oral communications under this act and fail the test established in Katz where one who is speaking in the actual presence of a police officer has neither a subjectively nor an objectively reasonable expectation of privacy. People in Interest of A.W., 982 P.2d 842 (Colo. 1999).

        Consensually overheard conversation not "eavesdropping". By the terms of CRS 18-9-304 (1)(a), a consensually overheard conversation is not eavesdropping. People v. Palmer, 652 P.2d 1092 (Colo. App. 1982) (Conversation between the informant and defendant was overheard by police officers via a transmitting device which the informant had consented to wearing.)

        Whether warrantless police eavesdropping violates the fourth amendment depends on whether the defendant had a justified expectation of privacy at the time and place of the communication. People v. Palmer, 888 P.2d 348 (Colo. App. 1994).

        CRS 16-15-102 allows law enforcement officers to intercept telephone communications after having obtained judicial authorization upon a showing of probable cause.  Affidavits in support of a request for an ex parte wiretap order must establish that there is probable cause to believe that evidence of specific enumerated crimes will be obtained through the substantial intrusion upon the individual's privacy. Identity of person allegedly committing offense must be included in application or affidavit.  People v. Montoya, 44 Colo. App. 234, 616 P.2d 156 (1980); People v. Martin, 176 Colo. 322, 490 P.2d 924 (1971).  The statute has been held constitutional. id., and not an unconstitutional invasion of privacy. People v. Milnes, 186 Colo. 409, 527 P.2d 1163 (1974).

        Under the Aguilar-Spinelli test, the affidavit must provide sufficient underlying circumstances to enable the magistrate to determine independently whether there is probable cause to believe that illegal activity is being carried on in the place to be searched and must set forth sufficient facts to allow the magistrate to determine independently that the informant is credible or his information reliable. People v. Montoya, 44 Colo. App. 234, 616 P.2d 156 (1980).  Probable cause ceases to exist when it is no longer reasonable to presume that the criminal activities are still being carried on in the place to be searched, and a warrant based on dated, or "stale", evidence is invalid.  id.

        Wiretapping is subject to pervasive federal and state regulation. See 18 U.S.C. §§ 2510-2520 (1970 & 1985 Supp.); CRS §§ 16-15-101 to -104, 8.  CRS 16-15-102(1)(a) provides that an ex parte order for wiretapping may be issued upon application by the attorney general or a district attorney, who establishes by affidavit that evidence will be obtained of a crime specified in section 16-15-102(1)(a). Detailed requirements for the application are set forth in CRS 16-15-102(2). The supporting affidavit serves the same function as an affidavit used to establish probable cause for a search warrant. People v. Corr, 682 P.2d 20 (Colo.), cert. denied, 105 S. Ct. 181 (1984). See CRS 16-3-303, -304; C.R.Crim.P. 41. The district court may enter an ex parte order authorizing wiretapping if it determines that there is probable cause to support the order. CRS 16-15-102(4).[fn4] The order must be specific as to the identity of the person whose communications are to be intercepted; the nature and location of the line to be monitored; the type of communication sought to be intercepted and the particular offense to which it relates; the agency authorized to intercept the communications; and the period of time during which interceptions are authorized. CRS 16-15-102(5).  People v. Watson, 53 P.3d 707 (Colo. App. 2001)

        CRS 16-15-102(2)(c) does not require that wiretapping be used only as a last resort and does not forbid the interception of all non-relevant conversations, but rather instructs the agents to conduct surveillance in such a manner as to "minimize" the interception of such conversations.  People v. Gable, 647 P.2d 246 (Colo. App. 1982).  Factors to consider in determining whether the agents have acted reasonably to minimize the interception of non-relevant conversations include: The nature and scope of the alleged criminal enterprise; the government's reasonable expectations as to the contents of, and parties to, the conversations; the degree of judicial supervision of the wiretap; the length of the conversations; the phase of the investigation; whether the parties used coded language; and the percentage of calls intercepted which are incriminating. Id.  The statutory requirements may be satisfied if the application informs the judge of the difficulties encountered and the lack of success or danger in using conventional investigatory methods. People v. Vazquez, 768 P.2d 721 (Colo. App. 1988), cert. denied, 787 P.2d 174 (Colo. 1990).

    The eavesdropping statute requires a case-by-case analysis as to whether the participants in the intercepted conversations have a justifiable expectation of privacy and, in turn, whether they believe that their conversation is subject to interception.  People v. Lesslie, 24 P.3d 22 (Colo.App. 2000)  The necessity of concealing the electronic listening device obviously leads to the conclusion that the participants to the conversations in the bathroom had an expectation of privacy, as well as a justifiable belief that their conversations were not subject to electronic interception.  Simply because a person allows one conversation to be overheard by nearby individuals does not mean that the expectation of freedom from electronic reception by any individual is objectively unreasonable.  id. at 28.

        A pen register is a mechanical device that records the numbers dialed on a telephone by monitoring the electrical impulses caused when the dial on the telephone is released. United States v. New York Telephone Co., 434 U.S. 159 (1977); People v. Sporleder, 666 P.2d at 135. A pen register records the date and time of the calls but does not monitor or record the contents of conversations. It does not indicate whether calls are actually completed and cannot determine the telephone numbers from which incoming calls were made.  People v. Watson, 53 P.3d 707 (Colo. App. 2001)

        By contrast, a wiretap records the contents of telephone communications. It also records the sound of electrical impulses created when a number is dialed on the monitored line. Expert analysis of the recorded sound can reveal the dialed numbers. A pen register, when used in conjunction with a wiretap, eliminates the need for analysis of the sound. The pen register is thus a technological refinement which merely expedites the determination of information already accessible to investigating officers by means of the wiretap. United States v. Kail, 612 F.2d 443 (9th Cir. 1979), cert. denied, 446 U.S. 912 (1980); United States v. Falcone, 505 F.2d 478 (3d Cir. 1974), cert. denied, 420 U.S. 955 (1975).

        The use of pen registers is not governed by the wiretapping statute. People v. Wahl, 716 P.2d 123 (Colo. 1986).

        In United States v. New York Telephone Co., 434 U.S. at 159, the Supreme Court held that the use of pen registers is not subject to the restrictions of the federal wiretapping statute. The Court reasoned that the wiretapping statute is concerned only with the "interception" of the "contents" of communications, as those terms are defined in 18 U.S.C. §§ 2510(4) and (8).[fn5] Pen registers, the Court stated, do not "intercept" because they do not acquire the "contents" of communications.  A pen register discloses only the telephone numbers that have been dialed on the monitored line. The Court noted that its conclusion was supported by the legislative history of the wiretapping statute.[fn6] 

        Colorado's statute governing electronic surveillance is closely patterned after and designed to implement the policies of the federal act.  Federal authorities explaining the federal act should thus be accorded great weight in interpreting the Colorado statute. The definitions of "intercept" and "contents" contained in the Colorado statute are identical to those in the federal act. Compare 18 U.S.C. § 2510(4), (8) with CRS 16-15-101(3), (5). We have no reason on this issue to construe our statute in a manner contrary to the Supreme Court's interpretation of the federal act in United States v. New York Telephone Co., 434 U.S. at 159. Therefore, we hold that the use of pen registers is not governed by the wiretapping statute. Consequently, no separate order authorizing the installation of a pen register on the Ingram/Hinshaw line was required under the wiretapping statute.  People v. Watson, 53 P.3d 707 (Colo. App. 2001)

        However, use of a pen register is a search and seizure under article II, section 7 of the Colorado Constitution, and that the installation of a pen register therefore must be preceded by the issuance of a search warrant.  People v. Timmons, 690 P.2d 213 (Colo. 1984);  People v. Sporleder, 666 P.2d 135 (Colo. 1983)

        Not being subject to the wiretap statute, law enforcement may seek a warrant for a pen register in cases of prostitution, pimping, solicitation, pandering and the like.

        The inquiry is two prong.  
                1.) whether placement of the beeper is an invasion, and 
                2.) whether the monitoring is an invasion.

        The Supreme Court upheld the use of a beeper to monitor movements outside a home. United States v. Knotts, 460 U.S. 276 (1983)

        United States v. Karo, 468 U.S. 705 (1984) distinguished Knotts, supra, and held it inappropriate within the home.  The individual's expectation in the privacy of a residence] is plainly one that society is prepared to recognize as reasonable.

        Electronic beeper had been placed inside a can of ether; the government used the beeper to track the movements of the can over the course of several months. The defendants in Karo were eventually followed to a private residence suspected (correctly, as it turned out) of concealing a drug lab. Activation of the beeper revealed that the can of ether had been stored in the suspect home. At trial the defendants contended that the warrantless use of the beeper impermissibly intruded into the privacy of the home. The Supreme Court, distinguishing United States v. Knotts, 460 U.S. 276 (1983), agreed:

        Use of a flashlight to illuminate a vehicle lawfully stopped or parked on a public roadway does not constitute an illegal search.  United States v. Lara, 512 F.2d 209 (5th Cir. 1975); United States v. Lee, 274 U.S. 559, 71 L.Ed. 1202 (1927).  Diminished expectation of privacy surrounds the automobile because its contents are in plain view.  United States v. Chadwick, 433 U.S. 1, 97 S.Ct. 2476, 53 L.Ed.2d 537 (1977).  Flashlight used to illuminate contents of a trunk through an opening the width of a penny held to be a search.  Berryhill v. State, 372 So.2d 355 (Ala.Civ.App. 1979).

        Use of a bifocals, binoculars, field glass telescope or a similar device to magnify does not constitute an illegal search.  United States v. Lee, 274 U.S. 559, 71 L.Ed. 1202 (1927).  

        Under Katz, the focus will be whether one has an expectation of privacy, and if that expectation is reasonable.  See: 

1. State v. Abislaiman, 437 So.2d 181 (Fla. App. 1983)  (hospital emergency room parking lot surveillance camera zoomed on automobile - man with gun - lawful - diminished expectation of privacy in vehicle.)  A marijuana plant observed in the window would be different than a marijuana plant in a place in the interior where one would expect it to be secreted from view.  

2. United States v. Kim, 415 F.Supp 1252 (D.Haw. 1976).  FBI agents 1/4 mile away, viewed defendant's reading material through a 60 mm opening via an 800 mm telescope - held to be a search.

        Use of illumination or binoculars to improve the visibility of an object already in plain view has been held constitutional. See Texas v. Brown, 460 U.S. 730, 740 (1983) (plurality opinion); Fullbright v. United States, 392 F.2d 432, 434-45 (10th Cir.), cert. denied, 393 U.S. 830 (1968). But see United States v. Taborda, 635 F.2d 131, 137-39 (2d Cir. 1980) (holding that telescopic observation of the home "impairs a legitimate expectation of privacy")

        Held in Sundheim v. Board of Cty. Comm'rs, 904 P.2d 1337 (Colo. App. 1995):  It is undisputed that some of the investigator's observations were made from a public road outside plaintiffs' property. Because there is no invasion of privacy involved in observing that which is plainly visible to the public, a person's real property is not protected from observations lawfully made from outside its perimeter. Hoffman v. People, 780 P.2d 471 (Colo. 1989).  Neither are we persuaded that the use of a camera with a telescopic lens transforms this lawful observation into an unreasonable search. See United States v. Rucinski, 658 F.2d 741 (10th Cir. 1981); cf. United States v. Bassford, 601 F. Supp. 1324 (D. Me. 1985), aff'd, 812 F.2d 16 (1st Cir. 1987) (use of binoculars to enhance view of readily visible marijuana plants did not constitute unreasonable search); State v. Rogers, 100 N.M. 517, 673 P.2d 142 (N.M.App. 1983) (use of binoculars does not render aerial surveillance unconstitutionally intrusive).

        See:

        State v. Lewis, 296 Or. 57, 672 P.2d 708 (1983), where the court held that no invasion of any private interest occurred when the police used a telescopic lens to photograph the defendant through the living room window of his residence, merely amplifying the view that would have been visible from the public sidewalk. 

State v. Wacker, 317 Or. 419, 856 P.2d 1029 (1993), the court held that the use of a starlight scope to observe the defendant's activities in a car in the parking lot of a tavern, where patrons of the tavern were regularly passing within a few feet, was not a search. The use of the light-enhancing device merely aided the police in seeing activities that otherwise could have been seen with the naked eye by a bystander. In each of those cases, the character of the scrutiny by the government was held not to be sufficiently intrusive so as to constitute a "search." 

        A dissenting judge in United States v. Cusumano, 83 F.3d 1247 (10th Cir. 1996) stated:  I recognize that the use of illumination or binoculars to improve the visibility of an object already in plain view has been held constitutional. See Texas v. Brown, 460 U.S. 730, 740 (1983) (plurality opinion); United States v. Lee, 274 U.S. 559, 563 (1927); Fullbright v. United States, 392 F.2d 432, 434-45 (10th Cir.), cert. denied, 393 U.S. 830 (1968). But see United States v. Taborda, 635 F.2d 131, 137-39 (2d Cir. 1980) (holding that telescopic observation of the home "impair[s] a legitimate expectation of privacy").  

        Whether the search with visual aid is lawful without a warrant will depend upon the facts and circumstances

        What has been said with respect to the use of eavesdropping - wiretapping equipment is generally true as well as to electronic visual surveillance.  It is no search to videotape what a police officer is observing in plain view, nor is any justified expectation of privacy violated by videotaping of activity occurring in full public view.  Sponick v. City of Detroit Police Dept. 49 Mich. App. 162, 211 N.W.2d 674 (1973).  As a general proposition, when a police officer sees something in plain view from a vantage point at which he is lawfully present, the officer's observations do not constitute a "search" within the purview of the Fourth Amendment. 1 W. LaFave, Search and Seizures: A Treatise on the Fourth Amendment § 2.2 (2d ed. 1987). See People v. Donald, 637 P.2d 392 (Colo. 1981); People v. Gomez, 632 P.2d 586 (Colo. 1981).

        Closed circuit television along a public sidewalk or public park upheld.  See U.Mich.J.L.Ref. 571 (1980)

        Surreptitious placement of video camera in a place where defendant has a justified expectation of privacy is a search.  People v. Dezek, 107 Mich.App. 78, 308 N.W.2d 652 (1981) (stalls of public restroom); People v. Teicher, 52 N.Y.2d 638, 439 Y.Y.S.2d 846, 422 N.E.2d 506 (1980 (dentist's office).

        See Riley, 488 U.S. at 451 ("Any member of the public could legally have been flying over Riley's property in a helicopter . . . and could have observed Riley's greenhouse."); id. at 454-55 (O'Connor, J., concurring); Ciraolo, 476 U.S. at 213-14 ("The officers were able to observe plants readily discernible to the naked eye. . . . Any member of the public flying in this airspace who glanced down could have seen everything that these officers observed."); id. at 214-15 ("Justice Harlan's observations about future electronic developments . . . were plainly not aimed at simple visual observations from a public place." (emphasis added)); Dow Chem., 476 U.S. at 229, 231 ("Any person with an airplane and an aerial camera could readily duplicate them."); id. at 238 ("Although [the photographs] undoubtedly give EPA more detailed information than naked-eye views, they remain limited to an outline of the facility's buildings and equipment.").

        State v. Rogers, 100 N.M. 517, 673 P.2d 142 (N.M.App. 1983) (use of binoculars does not render aerial surveillance unconstitutionally intrusive) - cited in Sundheim v. Board of Cty. Comm'rs, 904 P.2d 1337 (Colo. App. 1995).

        Trial court ruled observation of the defendant's property from an airplane did not violate any reasonable expectation of privacy of the defendant. In so ruling, the court relied on California v. Ciraolo, 476 U.S. 207 (1986). Colorado Supreme Court dodged the issue, finding that information gleaned from the aerial survey is not necessary to the validity of the warrant.  Bartley v. People, 817 P.2d 1029 (Colo. 1991)

People v. Pollock, 796 P.2d 63 (Colo. App. 1990)

        FACTS:  Aerial surveillance of defendant's backyard from a helicopter 200 feet above the ground.  Defendant had erected an 8-foot solid wood fence around his backyard.  From this, it can reasonably be assumed that the 8-foot fence was placed to conceal defendant's backyard and its contents from at least street-level view. See California v. Ciraolo, 476 U.S. 207, 106 S.Ct. 1809, 90 L.Ed.2d 210 (1986). Thus, defendant exhibited an expectation of privacy in his backyard.  

1.         Defendant, his wife, and two neighbors testified that the extremely loud noise of the helicopter caused them to come outside to see what was happening and six other neighbors were seen outside looking at the helicopter. Indeed, defendant's ten-year-old daughter asked, "Is the army invading us?"  Thus, on this record, with unrefuted evidence, the type of which was notedly absent in both California v. Ciraolo and Florida v. Riley, we conclude that defendant had a reasonable expectation of privacy that no such surveillance would occur.

2.         Even the plurality in Florida v. Riley, 488 U.S. 445 (1988), while upholding the helicopter search at 400 feet, did not go that far. "Inspection of the curtilage from an aircraft [will not] always pass muster simply because the plane was within the navigable airspace specified by law.  Court noted that there was nothing in the record to suggest that helicopters flying at 400 feet were sufficiently rare that respondent could have reasonably anticipated that his greenhouses would not be observed at that altitude.

3.         Observations in Pollock held to be a search and the evidence suppressed.

Henderson v. People, 879 P.2d 383 (Colo. 1994)

FACTS:  Law enforcement received an anonymous telephone call informing that defendant had recently cultivated and sold marijuana from his residence.  The caller also stated that he observed $5,000 in cash, scales that are commonly used to weigh marijuana, and a number of weapons. Based on this information, police placed the residence under surveillance for several days but did not observe any illegal activity.  When he was unable to obtain a law enforcement helicopter, the officer entered into an agreement for the use of a helicopter operated by television station for a fly over of defendant's residential property. At an altitude of approximately 500' - 700', the helicopter made four or five passes over Henderson's residence during a period of approximately five minutes. The officer observed a plastic roof "with green plant material growing underneath the plastic."  Defendant was alerted by the over flights and police got a no-knock warrant.  Police seized evidence, including roots, stalks, leaves, and other remnants of marijuana as well as cultivation equipment and fertilizer. Guns, scales, plastic bags, a pipe, and a bag of marijuana were found inside the house.

1. The Fourth Amendment protects: "The right of the people to be secure in their persons, houses, papers, and effects against unreasonable searches and seizures." U.S. Const. amend. IV. "The basic purpose of this Amendment . . . is to safeguard the privacy and security of individuals against arbitrary invasions by government officials." Camara v. Municipal Court, 387 U.S. 523, 528 (1967). Therefore, warrants are generally required before a governmental agency or official may conduct a search. See United States v. Karo, 468 U.S. 705, 714-15 (1984) (stating that warrantless searches are presumptively unreasonable). 

2.         A warrant is only required, however, when a search occurs.  A search occurs when the government intrudes on an area where a person has a "constitutionally protected reasonable expectation of privacy." Katz v. United States, 389 U.S. 347, 360 (1967) (Harlan, J., concurring).[fn3] See also California v. Ciraolo, 476 U.S. 207, 211 (1986  (stating that a reasonable expectation of privacy is one that "society [is] willing to recognize . . . as reasonable"); Karo, 468 U.S. at 712 ("A `search' occurs `when an expectation of privacy that society is prepared to recognize as reasonable is infringed.'") (quoting United States v. Jacobs, 466 U.S. 109, 113 (1984)). In order to determine whether the expectation of privacy is reasonable or "what expectations of privacy are constitutionally `justifiable,'" United States v. White, 401 U.S. 745, 752 (1971), the facts and circumstances of each case must be analyzed to determine if the defendant's expectation of privacy is objectively reasonable. See Oliver v. United States, 466 U.S. 170, 177 (1984) (concluding that no single factor determines whether an individual legitimately may assert a claim under the Fourth Amendment that he should be free from governmental intrusion); United States v. Fisch, 474 F.2d 1071, 1077-78 (9th Cir. 1973) ("The test applied as to society's tolerance of the search rests, as it has for years, upon `the facts and circumstances — the total atmosphere of the case.' There is no ready formula, `each case is to be decided upon its own facts and circumstances.'") (footnotes omitted); Hoffman v. People, 780 P.2d 471, 474 (Colo. 1989) ("The existence of a legitimate expectation of privacy must be determined after examining all the facts and circumstances in each particular case.").

3.         The United States Supreme Court applied the totality of the facts and circumstances standard to determine if a defendant had a reasonable expectation of privacy in Florida v. Riley, 488 U.S. 445 (1988). In Riley, the Court determined that police observing the defendant's backyard from a helicopter flying at 400 feet did not conduct a search for Fourth Amendment purposes. 

4.         A plurality of the Court concluded that one of the primary factors in determining whether the defendant's expectation of privacy was unreasonable was that the helicopter was flying in navigable airspace within the Federal Aviation Administration (FAA) guidelines. Id. at 451. Thus, the Court relied on the fact that the observation itself was legal. In Ciraolo, the Supreme Court addressed the issue of the legality of a fly-over. The Court held that an aircraft used to view the defendant's backyard did not violate the defendant's reasonable expectation of privacy because the police were in legal airspace at an altitude of 1,000 feet viewing what any member of the public could observe from an aircraft.

In Henderson, the dispositive factors are that the marijuana was in plain view to anyone legally viewing the shed from the helicopter and the observation posed only a very limited degree of intrusiveness.  Defendant did not have a reasonable expectation of privacy in his marijuana and therefore the fly-over did not constitute a search under the Fourth Amendment to the United States Constitution.

        Bottom line - CSPD has a chopper, they fly regularly and what they can see is fair game.

        Thermal imager detects and records infrared radiation emitted from heat sources. Issue: Does warrantless use of the thermal imager to detect heat emissions from a residence violate the Fourth Amendment's proscription against unreasonable searches?

        Where the government, without seeking or obtaining a warrant, used a thermal imager to monitor the exterior of the Defendants' home and attached garage not subject to view by ordinary mean, the imager revealed multiple "hot spots" and that fact was included in an affidavit in support of a search warrant, the 10th Circuit Court of Appeals (Colorado) had the opportunity to address the above issue, but ruled that even in the absence of such information, the affidavit in support of a search warrant established probable cause.  The Court declined to rule on thermal imaging.  United States v. Cusumano, 83 F.3d 1247 (10th Cir. 1996).

McKAY, Circuit Judge, dissenting in part and concurring in part, with SEYMOUR, Chief Judge, and HENRY, Circuit Judge, joining: wrote:  

1. The fact that the thermal imager issue is now being routinely presented to the courts around the country demonstrates that it is not an issue of the future, but it is an on-going, widespread challenge to the privacy rights of America's citizens. The widespread use of thermal imagers today — even by law enforcement departments of limited financial means — is evidenced by the use of thermal imaging technology by the Sheriff's Department for Laramie County, Wyoming, in this case.

2. While the information obtained by the thermal imager in this case is relatively primitive (and the record in this case does not contain what we know about more invasive thermal imagers from the media), this court's decision should be based upon a principled analysis rather than on whether the search in the present case turned up alarmingly personal information. After all, the evil of the warrantless entry of officers into one's house does not turn on what they find, but that the government invaded a citizen's house on a warrantless basis. 

3. In some instances the government is using the thermal imager to invade the privacy of innocent by-standers. The law enforcement "experts" reading the information from the thermal imager use the device against the homes of those who live nearby the criminal suspect to establish a baseline. See, e.g., Robinson, 62 F.3d at 1327; Robertson, 39 F.3d at 893. Using the thermal imager in this manner is inherently nefarious because all of us are susceptible to having the private activities within our homes intruded upon by the government by merely living near one suspected of criminal activity. 

4. If we permit information obtained by thermal imaging to be considered waste, abandoned, or to be characterized as having some other non-protected legal status, then we not only permit unwarranted invasions by the police but analytically destroy civil remedies against privacy invaders such as the paparazzi and tabloid photographers. Our failure to draw the line at this first and primitive warrantless invasion would make it particularly difficult to protect against the use of "passive" devices of the future that would invade the privacy of our chambers or that would re-create the full range of the activities in our homes by way of computer-assisted images broadcast at the station house, at the newsroom of the local press or television station, or on the Internet. This modest parade of the horribles is not fanciful: Any user of the Internet or follower of the news media is aware of the fact that the Brave New World is at hand.

5. There is no question but that activities which take place within the sanctity of the home merit the most exacting Fourth Amendment protection. It is likewise undisputed that the illegal conduct which produced the heat detected by the thermal imager was performed within the four walls of the Defendants' home.  It must, finally, be acknowledged that the heat gradients measured by the imager radiated beyond the confines of the home.

6. To focus upon the "waste heat" radiating from a structure is to ignore both the purpose of the device and the manner in which it operates. The imager measures not "waste heat" but rather heat differentials; it records heat gradients across the exterior surface of a building. The laws of thermodynamics inform us that the amount of heat radiated from a given section of the exterior wall is directly related to the amount of heat generated by heat sources in proximity to the interior of that wall. Activities that generate a significant amount of heat therefore produce a heat "signature" that the imager can detect.  Under optimal conditions — viewing through an open window into a darkened room, for example — the imager (or one much like it) might well be able to resolve these heat signatures into somewhat indistinct images.  See, e.g., Young, 867 P.2d at 595 (noting that an imager can discern a human form through a curtained window under certain circumstances). More typically, the machine identifies only hot spots on a wall (as was true in this case). In either instance, it is the existence of these distinct interior sources that the device indirectly recognizes — with greater or lesser imprecision varying with the insulating attributes of the exterior walls — and records. While the heat lost by a building is data of some limited value,[fn17] the true worth of the device — the very reason that the government turned the imager on the home of the Defendants — is predicated upon the translation of these thermal records into intelligible (albeit speculative) information about the activities that generate the observed heat. The utility of the machine depends therefore not on the inevitable and ubiquitous phenomenon of heat loss but on the presence of distinguishable heat signatures inside the structure. I see no reason to blind ourselves to the physical reality of this relationship by severing our analysis of the heat differentials emanating through the walls of a structure from an informed consideration of the heat sources within that structure.

7. There is an obvious distinction between common tools that enhance vision (e.g. illumination or binoculars) and a sophisticated instrument that observes infrared radiation.

8. Dissent clearly stats that in the warrantless thermal imaging, constitutional error occurred..

        Other courts that have analyzed this question have split. The Seventh and Eighth Circuits recently embraced the analysis set forth in United States v. Penny-Feeney, 773 F. Supp. 220 (D. Haw. 1991), aff'd on other grounds, 984 F.2d 1053 (9th Cir. 1993), holding that the use of an imager is not a search within the meaning of the Fourth Amendment. See United States v. Myers, 46 F.3d 668 (7th Cir. 1995); United States v. Pinson, 24 F.3d 1056 (8th Cir.), cert. denied, 115 S.Ct. 664 (1994).  The Eleventh Circuit, in United States v. Ford, 34 F.3d 992 (11th Cir. 1994), reached the same conclusion, albeit for slightly different reasons. 

        The Fifth Circuit has rejected aspects of the Penny-Feeney and Ford frameworks, but, drawing upon the "open fields" doctrine, nonetheless has held that a thermal scan of a building outside the curtilage does not qualify as a Fourth Amendment search. See United States v. Ishmael, 48 F.3d 850 (5th Cir. 1995). 

        The Supreme Court of Washington, interpreting both the Fourth Amendment and the relevant sections of the Washington Constitution, has determined that the warrantless use of a thermal imager runs afoul of both constitutions. State v. Young, 867 P.2d 593 (Wash. 1994).

        A thermal imager operates by observing and recording the differential heat patterns radiating through the surface of a structure.  Focusing upon this most basic aspect of the imager's operation, the circuits have reduced the Fourth Amendment inquiry to an analysis of the reasonable expectations of privacy residing in this "waste heat." See Ishmael, 48 F.3d at 853-57; Ford, 34 F.3d at 995-97; Pinson, 24 F.3d at 1058-59; Penny-Feeney, 773 F. Supp. at 225-28. A number of justifications have been put forth to support the conclusion that no expectation of privacy, either objective or subjective, exists in "waste heat." The observation of "waste heat" has been analogized to the garbage search approved in California v. Greenwood, 486 U.S. 35 (1988); to the dog sniff found constitutional in United States v. Place, 462 U.S. 696 (1983); to the pen register condoned by Smith v. Maryland, 442 U.S. 735 (1979); and to the overhead surveillance flights upheld in California v. Ciraolo, 476 U.S. 207 (1986); Dow Chem. Co. v. United States, 476 U.S. 227 (1986), and Florida v. Riley, 488 U.S. 445 (1989). It has been noted that (1) the thermal imager is a passive device, employed from beyond the curtilage, which emits no rays or beams and which does not intrude in any fashion upon the observed property; (2) the resolution of the device is limited and that, in general, it detects only hot spots on the exterior surfaces of a building; (3) in many cases the machine measures heat which has been actively vented from a structure by a defendant; and (4) the machine only observes a phenomenon that could be watched by any member of the public equipped with a similar instrument (which is commercially available).

Copyright © 1996 - All Rights Reserved - Document Revised: October 01, 2009
no copyright claimed to merchant logo, software logo, flag, envelope or drawing images