May 24, 2016
from the United States District Court for the Eastern
District of Wisconsin. No. 13-CR-234 Rudolph T. Randa, Judge.
WOOD, Chief Judge, and Easterbrook and Kanne, Circuit Judges.
Easterbrook, Circuit Judge.
in Wisconsin arrested Damian Patrick while he was in a car on
a public street and found him armed. That led to this federal
prosecution, because Patrick's criminal record made it
unlawful for him to possess firearms. 18 U.S.C.
§922(g)(1). The district court denied his motion to keep
the gun out of evidence. 2015 U.S. Dist. Lexis 1421 (E.D.
Wis. Jan. 7, 2015), approving a magistrate judge's
recommendation, 2014 U.S. Dist. Lexis 179522 (E.D. Wis. Sept.
30, 2014). Patrick pleaded guilty but reserved the
opportunity to contest the validity of his arrest, and thus
the validity of the gun's seizure. He now appeals from
the 57-month sentence he received.
was serving a term of parole that followed his release from
state prison. He did not comply with the conditions of his
release, and a warrant was issued for his arrest. (He does
not contest that warrant's validity.) In an effort to
find Patrick, Milwaukee's police obtained a second
warrant, which authorized them to locate Patrick using
cell-phone data. Patrick's cell phone revealed his
location, which enabled the police to find him.
attempts to undermine the validity of the location-tracking
warrant by contending that his person was not contraband or
the proceeds of a crime, and that it therefore was off limits
to investigation. That sounds like an attempt to resurrect
the "mere evidence" doctrine that the Supreme Court
disapproved in Warden v. Hayden, 387 U.S. 294
(1967). Hoyden authorized the use of warrants to get
evidence to locate a wanted person. See also Steagald v.
United States, 451 U.S. 204 (1981) (search warrant to
enter house to look for person to arrest). Police were
entitled to use a warrant to obtain data that would help them
track down Patrick's location.
they were entitled to arrest him without a warrant of any
kind, let alone the two warrants they had. United States
v. Watson, 423 U.S. 411 (1976), holds that probable
cause alone is enough for an arrest in a public place. A
warrant is necessary only when the police need to enter a
private area to capture the wanted person. See Payton v.
New York, 445 U.S. 573 (1980). Because Patrick was
visible to the general public, he did not have any privacy
interest in his location at the time.
the Supreme Court recently held that a valid arrest warrant
precludes the suppression of evidence seized in an arrest,
even if the arrest was set in motion by officers who had
neither probable cause nor knowledge of the warrant. Utah
v. Strieff, 136 S.Ct. 2056 (2016). Strieff
tells us that, if the police had stopped Patrick's car
for no reason at all and learned only later that he was a
wanted man, the gun would have been admissible in evidence.
The officers who nabbed Patrick, by contrast, had both
probable cause to believe that he was a fugitive from justice
and knowledge of the arrest warrant. The gun cannot be less
admissible than in Strieff, even if we knock out the
means used to track his location.
Patrick was arrested in a public place, and the arrest was
supported by both probable cause and a valid arrest warrant
that had been issued before any effort to learn his location
(an effort that therefore could not "taint" the
arrest in the parlance of the exclusionary rule), we need not
resolve some difficult issues posed by a fact that came to
light while the case was in this court. After Patrick filed
his opening brief, the prosecutor revealed that Patrick's
location had been pinned down using data from a cell-site
simulator. That device (often called a Stingray, the
trademark of one brand) pretends to be a cell-phone access
point and, by emitting an especially strong signal, induces
nearby cell phones to connect and reveal their direction
relative to the device. Here is a description from the
Department of Justice:
Cell-site simulators ... function by transmitting as a cell
tower. In response to the signals emitted by the simulator,
cellular devices in the proximity of the device identify the
simulator as the most attractive cell tower in the area and
thus transmit signals to the simulator that identify the
device in the same way that they would with a networked
A cell-site simulator receives and uses an industry standard
unique identifying number assigned by a device manufacturer
or cellular network provider. When used to locate a known
cellular device, a cell-site simulator initially receives the
unique identifying number from multiple devices in the
vicinity of the simulator. Once the cell-site simulator
identifies the specific cellular device for which it is
looking, it will obtain the signaling information relating
only to that particular phone. When used to identify an
unknown device, the cell-site simulator obtains signaling
information from non-target devices in the target's
vicinity for the limited purpose of distinguishing the target
By transmitting as a cell tower, cell-site simulators acquire
the identifying information from cellular devices. This
identifying information is limited, however. Cell-site
simulators provide only the relative signal strength and
general direction of a subject cellular telephone; they do
not function as a GPS locator, as they do not obtain or
download any location information from the device or its
applications. Moreover, cell-site simulators used by the
Department must be configured as pen registers, and may not
be used to collect the contents of any communication, in
accordance with 18 U.S.C. §3127(3). This includes any
data contained on the phone itself: the simulator does not
remotely capture emails, texts, contact lists, images or any
other data from the phone. In addition, Department cell-site
simulators do not provide subscriber account information (for
example, an account holder's name, address, or telephone
of Justice Policy Guidance: Use of Cell-Site Simulator
Technology (Sept. 3, 2015) at 2. See also the Wikipedia entry