On 9/3/13 2:47 PM, Tom Van Baak wrote:
Nowhere does the opinion mention if the timestamps were taken on
the same clock or if the two clocks were synchronized.
PHK,
Correct. This is an age-old problem, whether its minutes or
nanoseconds. Time-stamps are inherently relative to a local
oscillator's time and rate offset, and affected by frequency drift
and stability levels.
A solution to this problem is for the "first responder" to take the
cell phone(s) and simultaneously send a text message to himself from
each phone. That could help establish a legal time difference
(unless, there are variable reception or carrier-specific delays).
No way is the FR going to do anything with that phone other than drop it
into a shielded bag, maybe after removing the battery.
Operating the keys on the phone would be "tampering with the evidence".
They could also simultaneously send cell phone photos of a handheld
GPS receiver's time display. That could help establish a legal time
accuracy question (unless, the cell phone or GPS receiver were in
some sort of hold-over mode).
If that's the case, it would be done in a forensic lab with the phone
hooked up to one of those fancy phone analysis systems.
For extra credit, further photos can be sent each hour for hours or
days to determine the cell phone frequency drift and stability
parameters.
Then again, realize that a jury of your fellow citizens, not a jury
of your "peers", will decide the question of timing. Thus to raise
technical issues like syntonization vs. synchronization, or standard
vs. Allan deviation, or GPS vs. UTC clocks will probably not help
your case.
There's a whole literature of mystery novels based on timetables and
such, including clever use of that new fangled device the telephone to
make someone think they are in one place rather than another.
WHen *I* commit that perfect murder, and am unhappily arrested, I'm
going to demand that only time-nuts sit on the jury. You've been
warned. The Ventura county courthouse is in a fairly pleasant location
near the shore and has a decent cafeteria. Pray I do not get arrested
in Los Angeles county, which is a hellhole in which to serve as a jury
member.
Realistically, though, there's a lot of potential time related
litigation in the securities industry. Accusations of "front running"
in the high frequency trading area, for instance, might revolve around
milliseconds.
For all we know, there are litigation consultants reviewing the archives
of this list at this very moment, identifying people who they would or
would not want sitting on the jury.
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