What's the worst case scenario for an owner of an unsecured wireless network? It's probably a mooching neighbor downloading child porn, leading the police to your doorstep. That's what happened here, and after the police searched the homeowner's computers, finding nothing, they used a tool called the "MoocherHunter" to track down the true offender, Richard Stanley.
The question is: is tracking signal strength to a person's doorstep a "search" under the Fourth Amendment? The Supreme Court has ruled that using infrared to detect heat signals coming from one's home was, and this would seem to be the same situation.
Only, according to the Third Circuit, it wasn't.
Tech Makes for Interesting Fact Patterns
Let's start with the file sharing network, which in this case was Gnutella. Gnutella users have their own unique software ID number. This number was traced back to the Comcast IP address of the homeowner with an unsecured wireless network.
From there, after searching the homeowner's computers and router, the police investigator found the MAC address of the mooching neighbor who was suspected of being the culprit. A police computer was attached to the router to lie in wait for the neighbor to reconnect. When the neighbor did, and again began sharing child porn on the Gnutella network, the investigator was able to verify the MAC address and eliminate the homeowner as a suspect.
He then used the MAC address, along with a tool called the MoocherHunter, to track the signal strength coming from the wireless user's device. The closer he got to the defendant's apartment door, the stronger the signal got. At this point, the police obtained a warrant, searched the home, and found 144 images and video files depicting child pornography.
Invasion of Privacy?
In Kyllo v. United States, the Supreme Court held that the use of "sense-enhancing technology" (infrared) to obtain "information regarding the interior of the home that could not otherwise have been obtained without physical intrusion into a constitutionally protected area constitutes a search," where the technology used in in "general public use."
That sounds like this case, right? The MoocherHunter, which is available to the public, is sense-enhancing technology that allowed the police to find the MAC address inside of a constitutionally protected home.
But, in Kyllo, the defendant sought to contain his marijuana-growing activity inside his home, justifiably relying on the privacy protections afforded one's home. Here, Stanley was deliberately projecting his internet signal outside of his home in order to share child pornography with others:
"In effect, Stanley opened his window and extended an invisible, virtual arm across the street to the Neighbor's router so that he could exploit his Internet connection. In so doing, Stanley deliberately ventured beyond the privacy protections of the home, and thus, beyond the safe harbor provided by Kyllo."
The Third Circuit panel also held that his expectation of privacy would not be justifiable, since he likely violated state law by hijacking his neighbor's Internet access:
"Stanley cannot conceal his location by establishing an unauthorized connection and at the same time ask society to validate his expectation of privacy in the signal-strength information," Judge D. Brooks Smith wrote. "Although the analogy is imperfect, we believe that the MoocherHunter is akin to a drug sniffing dog in that it was only able to detect a signal that was itself unauthorized and likely illegal."
Do you buy the distinction between infrared searches and tracing a wireless signal back to a person's hardware? Tell us your thoughts @FindLawLP.
- United States v. Stanley (FindLaw's Caselaw)
- Using a Virtual Child to Catch Web Cam Predators; Is It Legal? (FindLaw's Technologist Blog)
- Alleged Pedo's Computer Gets Locked by Virus, Turns Himself In (FindLaw's Technologist Blog)