Dave Hinz wrote:
On Tue, 02 May 2006 14:21:38 -0500, Jon Elson wrote:

You think this is funny! For 911 response purposes, the cell phone
companies are
required to triangulate the location of all phones every couple of
minutes from
the several cell sites that can "hear" the phone, whenever it is turned
on to be
able to receive calls.


Really?


(The newer phones have GPS receivers in them,
and the
cell sites interrogate the phones for location every couple of minutes.)
The cell
phone companies are required to keep this location tracking data for 7
years for
law enforcement purposes.


Cite, please?
OK, there was a murder in 2004 in Des Peres, MO (less than a mile from
my home) where a family member drive from NC, I think, to bump off an
abusive brother in law. The abused woman had her sister buy a cell
phone for her, and made the transaction as untracable as they could,
paid in cash, etc. The murderer borrowed the phone to stay in touch
during the operation, and left the phone on during the whole drive so
he could be contacted if there was any complication to the plot. Expert
testimony from the cell phone co. was presented pinpointing the location
of the guy all along the travel route, and right up to the vicinity of
the murder site, and then heading immediately back to NC. No
authorities had any idea about the plot until days after the murder was
committed. So, the tracking data for ALL phones must have been kept
for months after the murder, until the authorities came with a subpoena.

There have been a couple of other murder investigations where cell phone
tracking info was presented, too.

Jon