Judge Tackles Police Use Of Radar To Scan Home Interiors And Comes Up With No Real Answers

from the it-comes-down-to-details-and-there-just-aren't-enough-of-those dept

Being in law enforcement often means brushing right up against the edges of the Fourth Amendment. It's your job to catch criminals, and most criminals have zero interest in being caught. The resulting surface tension is easily broken. Some breaks are inadvertent. Others are much more deliberate. But in this case, the circumstances are ambiguous at best.

A recent case presided over by Judge Neil Gorsuch of the Tenth Circuit Court deals with these stretched edges. [via Orin Kerr] Convicted felon Steven Denson stopped meeting with his probation officer and holed up in his house, where he was subsequently arrested for parole violations and the illegal possession of firearms. (The guns hadn't been used in any criminal activity, but Denson's previous felony conviction made it illegal for him to possess them.)

We know Denson was in his house because the end result bears that out. Leading up to the entrance of his residence, the police gathered other information indicative of Denson's whereabouts: utilities registered in his name, his lack of employment and electricity usage that surpassed that of an empty house.

Denson challenged the arrest and the post-arrest seizure of weapons on the basis of a single act performed by the officers prior to entry: the use of Doppler radar to determine whether someone was actually on the premises.

While it's never specifically stated as such, the gist appears to be that the Doppler radar was considered a warrantless search by Denson -- something that should negate the actions of the officers following the radar's use. The police had no warrant to search the premises, only a warrant to effect an arrest. While he was being arrested, police swept his home (without a warrant), uncovering the illegal weapons. Judge Gorsuch -- after some discussion on whether the police had enough "probable cause" to believe Denson was at home -- tackles the issue of the radar itself, something that presents Fourth Amendment concerns. [pdf link]
Separately and as we alluded to earlier, the government brought with it a Doppler radar device capable of detecting from outside the home the presence of “human breathing and movement within.” All this packed into a hand-held unit “about 10 inches by 4 inches wide, 10 inches long.” The government admits that it used the radar before entering — and that the device registered someone’s presence inside. It’s obvious to us and everyone else in this case that the government’s warrantless use of such a powerful tool to search inside homes poses grave Fourth Amendment questions. See, e.g., Kyllo v. United States, 533 U.S. 27, 33-35 (2001) (holding that using warrantless thermal imaging to show activity inside a home violated the Fourth Amendment) New technologies bring with them not only new opportunities for law enforcement to catch criminals but also new risks for abuse and new ways to invade constitutional rights.
Denson argues the police had no reason to enter his home, much less search it. The only reason they did was because the Doppler radar indicated someone was in the house. He also argues that the use of the radar should have negated the officers' stated need to perform a sweep of the house for other individuals -- this protective sweep being the instrument of discovery for Denson's weapons stash.

The single mention of a precedential case (Kyllo v. United States) is inserted near the discussion about "grave Fourth Amendment questions," and never mentioned again. It would appear that the Doppler radar was a warrantless search of Denson's premises, at least under this Supreme Court ruling, but Gorsuch ignores this and focuses on the probable cause factors justfying entry of the home in the first place.

Gorsuch examines the protective sweep more closely, and finds it wanting, considering the pre-entry radar deployment. On one hand, Denson's history of violent crime and known violent criminal associates would have justified a "protective sweep" during his arrest. But, on the other hand, the cops already knew no one else was on the premises.
But what — again — about the radar? Before the officers entered, their radar search suggested the presence of one person inside. And given that, one might well wonder: did the officers’ questionable search outside the home paradoxically negate their otherwise solid case for a search inside the home? Surely, after all, the government isn’t entitled to perform searches to guard against phantom risks, ones they know don’t exist. If radar (or any other investigative technique for that matter) dispels the possibility of a hidden danger, a search predicated on that possibility becomes constitutionally unreasonable.

The government cannot take the benefit of a questionable radar search without having to live with its costs. Neither does the government seek to justify its protective sweep in this case on the presence of any threat (say, traps or bombs) that its radar wasn’t designed to detect. The government’s only professed fear was the presence of persons, something its radar was admittedly designed to detect.
Gorsuch could have pushed a bit more on this point, but unfortunately, defers to the unknown.
Even so, without more facts about the radar, its capacities and how it was used, we just can’t say it “dispel[led]” the officers’ “reasonable suspicion of danger” in this case. We know the radar suggested the presence of someone inside. But how far inside the structure could it see? Could the device search the whole house and allow the officers to be sure that they had located every person present? Could it distinguish between one person and several? We just don’t know. Our record lacks any answers. As a result, we simply aren’t in a position to say that the radar search negated the officers’ otherwise specific and articulable reasons to worry about a compatriot lurking inside.
And that's where it ends. Gorsuch notes that the use of these devices means this sort of thing will be discussed again. As for the police department, it's safe to assume it isn't interested in divulging further details about its technology, even if what it withholds may jeopardize the evidence it obtained.

But behind it all, there were two searches performed -- both without a warrant. First, there was the Doppler "search," which determined someone was home. Then there was the search performed under the guise of a "protective sweep." The guns were uncovered in a closet, something that would be checked during a sweep, but the question falls back to whether the sweep itself was justified. Gorsuch says basically that he just doesn't know and the question remains open until the situation presents itself again.

The troubling aspects about the Doppler radar align with concerns about Stingray devices. Police have used IMSI catchers to track down suspects without having to deal with search warrants -- something radar can do as well. In both cases, details about capabilities are left to the courts' imaginations. No one in law enforcement wants to talk about the level of intrusion or the inherent limits of the tech and, for the most part, their silence has been unchallenged.

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  1. icon
    mattshow (profile), 21 Jan 2015 @ 4:08pm

    Re: Re:

    But the judge doesn't know. The judge is not an expert on how these radar guns work. And there are limits on how much independent investigation judges are allowed to do. They are generally expected to work with what has been put on the record: the evidence introduced by the parties.

    If the defendant's lawyer was going to argue that the use of these radar guns was unconstitutional, (s)he should have made sure the judge was educated on just how these guns work.

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