United States v. Alexander Norris
942 F.3d 902
9th Cir.2019Background
- FBI downloaded child pornography from P2P username “boyforboys1” associated with various IP addresses; AT&T records tied one IP to Apartment 242, leading to a warrant and search of Apt. 242 that yielded no contraband.
- Agents found two unknown devices (MACs “CK” and “bootycop”) had connected to the Apt. 242 password-protected router; residents could not identify them.
- Using Moocherhunter (wireless-tracking software) plus a directional antenna, agents took signal-strength readings for target MAC addresses from outside Apt. 242 and concluded the signals pointed to Apartment 243.
- Subsequent downloads from the target username showed distribution via the router IP tied to Apt. 242; on-site checks confirmed the unknown devices had connected to that router earlier.
- Based on the Moocherhunter readings, agents obtained a warrant for Apt. 243 and found child pornography there; Norris was indicted, moved to suppress and for a Franks hearing, was denied, convicted, and appealed.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Whether use of Moocherhunter to locate a device's MAC/signal constituted a Fourth Amendment search | No search: agents collected information from public/non‑protected spaces; no physical intrusion; Katz controls | Use of wireless‑tracking software to identify a device's location is a warrantless search implicating Katz/Kyllo/Jardines protections | No search; Katz applied and no Fourth Amendment search occurred |
| Whether Norris had a subjective expectation of privacy in the MAC signal strength | No: transmission to and reception by a third‑party router exposed the signal; unauthorized access assumed the risk | Yes: device located inside home; transmissions originate from within the residence and should be private | No subjective expectation of privacy in the externally emanating signal |
| Whether society is prepared to recognize that expectation as reasonable | Not reasonable: expectation based on unauthorized use of a third‑party, password‑protected router is not legitimate | Reasonable: privacy interest exists even if signal travels outside home | Not reasonable; society would not recognize privacy in signals generated by unauthorized access |
| Whether Norris made a substantial preliminary showing warranting a Franks hearing about alleged falsehoods/omissions in the affidavit | Affidavit was sufficient; any inaccuracies/omissions were not intentional/reckless nor material to probable cause | Affidavit mischaracterized Moocherhunter and omitted material information (free vs. law‑enforcement version, testing, training, anomalous readings) warranting an evidentiary hearing | Denied: Norris failed to show intentional/reckless falsity and corrections/omissions would not negate probable cause |
Key Cases Cited
- Katz v. United States, 389 U.S. 347 (1967) (establishes two‑part reasonable-expectation-of-privacy test)
- Florida v. Jardines, 569 U.S. 1 (2013) (physical intrusion onto curtilage to gather evidence is a search)
- Kyllo v. United States, 533 U.S. 27 (2001) (use of sense‑enhancing tech to learn details of home interior is a search)
- United States v. Karo, 468 U.S. 705 (1984) (monitoring a device that reveals information from inside a home can be a search)
- Franks v. Delaware, 438 U.S. 154 (1978) (standard for obtaining a Franks evidentiary hearing challenging warrant affidavits)
- United States v. Stanley, 753 F.3d 114 (3d Cir. 2014) (Moocherhunter case reaching similar conclusion on no legitimate privacy in MAC signal)
- United States v. Caymen, 404 F.3d 1196 (9th Cir. 2005) (no Fourth Amendment protection for contents of stolen property)
- United States v. Borowy, 595 F.3d 1045 (9th Cir. 2010) (exposure of files/content via public file‑sharing is not protected)
- California v. Ciraolo, 476 U.S. 207 (1986) (observations from public airspace not a search)
- California v. Greenwood, 486 U.S. 35 (1988) (items knowingly exposed to public lack Fourth Amendment protection)