Court Upholds “Geofence” Warrant for Information on Phones Near a Crime | Hacker News Reader

Court Upholds “Geofence” Warrant for Information on Phones Near a Crime

reason.com

17 pointshirundo8 comments

A dissent using a slightly altered scenario, you see a killing on a security cam, and the killer puts a knife in their briefcase on camera then you have the police stop everyone in a 2 mile radius and break into their briefcase rifle through their documents and arrest people based on the findings, you might catch the killer but you have trampled the rights of everyone in the zone. The density of the zone shouldn't matter, if it is on Wallstreet or a field in Kansas it is equally wrong. A range is not a particular place and they didn't identify the people as stated:

"[t]he right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."

It clearly says "AND". They don't know who or what they are targeting and the 4th clearly protects that.

> break into their briefcase rifle through their documents

I think I gave you that misleading impression by poorly abbreviating the headline. The warrant was not for the contents of the phones, but for identities of people carrying them nearby at that those times. IANAL but I think another warrant would be needed to search the phone or individual.

A log of my whereabouts and activies I consider my personal document, exactly the same as I consider a paper version stored in a briefcase. I took the false example from the article and adapted it rather than just using the headline.

"Imagine a homicide in an alley caught on a nearby surveillance camera. The video is clear enough to see the attack, but too grainy to identify who did it. It is obvious from the video, however, that the perpetrator is checking his cell phone as he walks out of the alley. Having determined the location and time of the killing from the video, would it be lawful for the police to obtain a warrant leveraging the tracking capability of mobile devices to identify whose cell phone was in the area of the crime when it occurred?"

In this case I swapped a digital briefcase for a physical one. If I hire someone to carry my briefcase it does not negate my right to the protection of it or its contents.

Expect a google-takeout.zip to be sent.

It seems like a good thing to search all the people with a similar briefcase in the area. This will directly help to resolve the case and reassure the population that the police takes the situation very seriously.

Searches require warrants. The fourth has specific criteria, requiring specific location and people or items.

A geofence fails that criteria because it doesn't say who is to be searched, it also has an overly broad place.

An address explicitly listing buildings is half of appropriate criteria, a city block is not. A 2 mile radius is not.

The other half is the specific people or items.

> The video is clear enough to see the attack, but too grainy to identify who did it. It is obvious from the video, however, that the perpetrator is checking his cell phone as he walks out of the alley.

Use a fake phone like an ipod touch to waste investigator's time and pin it on the nearest person with an outstanding warrant.

Have fun with the Innocence Project! "acquittal" never seems to mean "find the accurate perpetrator"

Very informative article. I have two questions:

1. Is the multistep personal identification process listed in the court papers the same for all geofencing warrants?

2. How successful are these things in actual use?

The process described seems far less problematic that it would seem without knowledge of the process. But the court documents show that Google only claims to be able to accurately locate 67% of devices running their apps. And, it seems, that this translates to even fewer smartphone users. If you have an iPhone, Google might not even see you unless you are directly using their apps during the timeframe within the warrant. A lot of people turn off background refresh, and if you don't there is still no guarantee that iOS will allow the app to run in the background during that timeframe.

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