The Volokh Conspiracy

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Two district courts adopt the mosaic theory of the Fourth Amendment


Regular readers will recall the mosaic theory of the Fourth Amendment introduced by the DC Circuit in United States v. Maynard, by which law enforcement steps that aren't searches in isolation can become searches when aggregated over time. For the most part, judges have been pretty skeptical of the mosaic theory. For example, in the recent oral argument in the Fourth Circuit in United States v. Graham, on whether the Fourth Amendment protects historical cell-site data, the mosaic arguments didn't gain a lot of traction for the defense.

In this post, however, I want to focus on two recent federal district court decisions that cut against this trend and adopted the mosaic theory. The first case is United States v. White (E.D.Mich. Nov. 24, 2014) (Lawson, J.), which held that the Fourth Amendment was violated when the government obtained a warrant to track a drug dealer's cell phone continuously over 30 days. The second case is United States v. Vargas (W.D.Wash. Dec. 15, 2014) (Shea, J.), which suppressed video evidence from a camera set up on a public utility pole 100 yards away from the target's rural house that showed what was happening on the target's front lawn continuously for six weeks.

1. United States v. White

In United States v. White, agents were conducting a wide-scale investigation into a known narcotics trafficker, Jimmie White. Agents obtained two search warrants to track White's cell phone in real time for 30 days each, with the goal of understanding the scope of White's activities and to show his involvement in narcotics crimes. When charges were brought, White moved to suppress the location information obtained from the cell phone location warrants. The case was heard before Judge David Lawson (who, allow me to add, I have had the pleasure of working with on the Criminal Rules Committee). Judge Lawson recognized that the Sixth Circuit had held in United States v. Skinner that monitoring a suspect's cell phone location in real-time was not a Fourth Amendment search. But Judge Lawson held that the facts of White's case were distinguishable:

[T]he surveillance in this case took place over an extended time period—continuously for 30 days on two (or three) separate occasions—and followed White into both public and private spaces. Justice Alito's concurring opinion in Jones, which drew support from a fifth justice, see Jones, 132 S. Ct. at 954-57 (Sotomayor, J., concurring), suggested that "the use of longer term GPS monitoring in investigations of most offenses impinges on expectations of privacy." Id. at 964 (Alito, J., concurring). The 4-week tracking in that case was well over the line of reasonableness, in his view. Ibid. ("We need not identify with precision the point at which the tracking of this vehicle became a search, for the line was surely crossed before the 4-week mark."). And the Skinner majority acknowledged Justice Alito's concerns, allowing that "[t]here may be situations where police, using otherwise legal methods, so comprehensively track a person's activities that the very comprehensiveness of the tracking is unreasonable for Fourth Amendment purposes." Skinner, 690 F.3d at 780. Skinner does not control the present case, because the length and breadth of the tracking here extends well beyond what any reasonable person might anticipate.

Judge Lawson then offered three reasons why 30 days of monitoring White's cell phone location violated his reasonable expectation of privacy. First, it included White's location when he was at home. Second, Congress has enacted statutory privacy protections for cell-site location. And third, 30 days of monitoring allows the government to obtain a detailed picture of a person's life. As a result, "it is safe to say that society would recognize that an interest in keeping these movements private is 'reasonable.'"

Judge Lawson recognized that his approach raised a difficult question of line-drawing: How long is long enough for monitoring to constitute a search? He answers:

[C]ourts have confronted similar problems in the past. For instance, how long may law enforcement detain property waiting for a drug detection dog to arrive for a sniff before the intrusion matures into a "seizure"? To find an answer, courts must "balance the nature and quality of the intrusion on the individual's Fourth Amendment interests against the importance of the governmental interests alleged to justify the intrusion." United States v. Place, 462 U.S. 696, 703 (1983).

Under that rationale, it may be appropriate to track an individual for a short time on public streets based on a level of suspicion that is less than probable cause. See Terry v. Ohio, 392 U.S. 1, 22 (1968) . . . Longer surveillances may require more justification, and a case might be made that the government's reasons underlying the need for tracking—in the case of domestic terrorism, for example—may call for less. The present case involves a garden-variety drug trafficking crime, nothing more. The blanket surveillance of an individual for thirty days at a time cannot equate to a brief detention, however. The "nature and quality" of an intrusion of that magnitude (in excess of the "the 4-week mark") tips the balance in favor of the individual; it constitutes a breach of one's reasonable expectation of privacy that requires the state to demonstrate probable cause as a justification for the intrusion. Jones, 132 S. Ct. at 964 (Alito, J., concurring).

This passage is interesting because it relies on caselaw concerning reasonableness, not what is a search. If I understand Judge Lawson correctly, he would say that even short-term monitoring on public streets is a search, but one that may be allowed based on only the Terry standard, at least depending on the crime under investigation. Here Judge Lawson goes significantly beyond Justice Alito's Jones concurrence, which had adhered to Knotts and indicated that short-term location monitoring is not a search at all.

Judge Lawson next concludes that no exceptions to the warrant requirement apply, so that a warrant is needed. But then he asks, what kind of warrant is sufficiently particular in its description of the place to be searched to allow real-time monitoring over an extended period? A warrant to follow someone everywhere is inherently general, he concludes, so a narrower warrant was needed:

The search warrant in this case allowed the police to track White at all times, night and day, on public streets and in private places, and into areas traditionally protected by the Fourth Amendment. . . . The government concedes that it tracked White even when he "was not on public thoroughfares." Gov.'s Resp. at 5. The warrant contained no minimization requirement, cf. 18 U.S.C. § 2518(5) (requiring communication intercepts authorized under Title III to "be conducted in such a way as to minimize the interception of communications not otherwise subject to interception under" law), or any other provision that defined "the discretion of the officer executing the warrant," Marron, 275 U.S. at 196, or "the limits of his power to search,'" Groh v. Ramirez, 540 U.S. 551, 561 (2004) (quoting United States v. Chadwick, 433 U.S. 1, 9 (1977)). The tracking warrants were akin to the general warrants condemned by the Founders, see Steagald v. United States, 451 U.S. 204, 220 (1981), and are repugnant to the Fourth Amendment.

Judge Lawson then concludes that even though the warrants in this case were general warrants that violate the Fourth Amendment, the good-faith exception to the exclusionary rule applies and the evidence can come in. Thus the motion to suppress is denied.

2. United States v. Vargas

In the second case, United States v. Vargas, the government set up a camera on a public utility pole about 100 yards from the defendant's rural home and used it to watch what was happening in his front yard continuously for six weeks. The government had reason to believe that the defendant's immigration status made it illegal for him to possess a firearm, and the video showed the defendant regularly engaging in target practice on his front lawn with his friends. The government obtained a warrant to search the defendant's home for firearms, which revealed several firearms and some crystal meth. When charges were brought before Judge Shea, Vargas moved to suppress the video evidence.

Before I get to Judge Shea's analysis in Vargas, it helps to know some pre-mosaic-theory law related to this issue. The Supreme Court has generally held that aerial surveillance from public airspace is not a Fourth Amendment search, although the cases are pretty murky in their reasoning. Lower courts have interpreted the Supreme Court's decisions in pretty murky ways, too. For the most part, lower courts have held that it's not a search for the government to conduct video monitoring of open fields or spaces not protected by fences, but there are some lower court opinions that say that it's a different situation if the video monitoring is from a point that the public generally won't see (like a view over a high fence) or if the video shows what is happening inside or at the edges of a home (in legal terms, the curtilage). For the details, see Section 2.3(g) of Wayne LaFave's Search And Seizure: A Treatise On The Fourth Amendment.

Okay, back to the Vargas case. Judge Shea suppressed the evidence from the video monitoring, ruling that the continuous video surveillance of the defendant's front lawn was a Fourth Amendment search that required a warrant. According to Judge Shea, the key was that "society expects that law enforcement's continuous and covert video observation and recording of an individual's front yard must be judicially approved." According to Judge Shea, it would have been lawful if the government had placed a human being on the utility pole and that person had watched the defendant's front lawn for six weeks. It would also have been lawful to fly a helicopter over the defendant's property and watch his front lawn. The reason using the camera was a search, according to Judge Shea, is that cameras are covert and catch everything: "This 'view' is so different in its intrusiveness that it does not qualify as a plain-view observation":

This dragnet law enforcement practice is not akin to either a naked-eye observation or a photographic picture by a live officer. Electronic surveillance by the government is increasing, and the need to balance this government tool with the Fourth Amendment is required. See Riley, 134 S. Ct. at 2484-85 (assessing the degree to which the search intrudes on an individual's privacy and the degree to which the search is needed to promote legitimate governmental interests).

As with White, it's interesting in Vargas to see caselaw from reasonableness invoked to answer what is a search. Traditionally, those inquiries are distinct. That is, courts traditionally consider what is a search, and only later consider whether and when a search is reasonable—the latter of which calls for a kind of cost/benefit inquiry while the former traditionally does not. In both White and Vargas, however, the district judges cite reasonableness caselaw to help explain what is a search, seemingly relying on an equilibrium-adjustment idea to expand the notion of what is a search in the first place.

Although parts of Judge Shea's reasoning is pretty general, other parts rely heavily on the rural location of Vargas's activity. Because Vargas lived in isolation, Judge Shea reasons, he could reasonably expect that he wasn't being watched when he was standing in his front yard:

Mr. Vargas reasonably believed that his frontyard activities would be private. Mr. Vargas chose to live in a rural area: an area mixed with farmland and undeveloped, sagebrush land. His rural home sits off a gravel road, and his front yard has a sense of enclosed space given a gated driveway and cyclone fence separating it from the gravel road. The USAO argues that any passerby could have seen Mr. Vargas' conduct. However, the setting of Mr. Vargas' home does not make the likelihood of a passerby likely: the road is gravel, his neighbors are "country neighbors," i.e., they live a distance away, and there are no public sidewalks. In addition, Mr. Vargas could hear a vehicle coming down the gravel road and modify his behavior, i.e., target practice would cease. in the presence of others.").

Unlike Judge Lawson in White, Judge Shea in Vargas did not conduct a "good faith" analysis. He moved straight from finding that the monitoring was a search to suppressing all of it.

What to make of Vargas? On one hand, I think it can be read narrowly as an extension of United States v. Cuevas-Sanchez, 821 F.2d 248 (5th Cir. 1987), which had held continuous video monitoring of the suspect's property was a search when conducted over a 10-foot high fence. The fence in Cuevas-Sanchez seems to have been more solid than in Vargas, so it seems that the video camera captured what a person could see if he had stationed himself on the public access road in front of Vargas's property while it's not clear that was the case in Cuevas-Sanchez. But it's at least somewhat similar. But then, looking back on it, Cuevas-Sanchez was itself pretty mosaic-y, so maybe even a slight extension of that case is noteworthy,

Alternatively, Vargas can be read broadly as trying to establish a general right to Fourth Amendment protection in public, at least in rural areas. For example, in a footnote, Judge Shea suggests that the use of drones in public space may also constitute a search in at least some cases. Specifically, in discussing drone legislation, he repeatedly uses the Fourth Amendment phrase "reasonable expectation of privacy" in discussing what drone legislation regulates. An excerpt:

The use of drones by law enforcement is another investigative practice that deviates greatly from "traditional" law enforcement investigative practices. Many states have adopted legislation to control the use of drones because a drone's ability to constantly and covertly view and record an individual or setting infringes on the American public's reasonable expectation of privacy that they will not be constantly and covertly observed by the government without a warrant. While seeking to protect this reasonable expectation of privacy, the drone legislation permits law enforcement to seek a judicial warrant to utilize a drone for investigative purposes[.]

I suspect the government will seek some kind of further review in the Vargas case, even if only to prompt Judge Shea to consider whether the exclusionary rule should apply in light of the good-faith exception. Or perhaps this case will tee up the mosaic theory for the Ninth Circuit, to the extent it doesn't address the theory in the Section 215 case recently argued before a panel of that court.

As always, stay tuned.