>
> In the States, it is apparently no use admitting digital
> photographs unless they
> have been digitally watermarked by some proprietory system, despite
> this not in
> itself helping at all.
Well that is the americans for you, classic case of over engineering
a solution to a problem.
> First off, (and assuming you know/care/guess/blag) do you think a
> sequence of
> JPEG images taken from a camera and stored on a computer be
> admissable as proof
> of someone's presence at a location? (There do appear to be
> 'forensic' methods
> of determining if a JPEG has been edited.)
Firstly I'd suggest you take a look at the Police and Criminal
Evidence Act (PACE), it is basically the bible when it comes to
handling of evidence for the UK Courts. Secondly the CPS acknowledge
that they can be used but there are problems, the main is tampering
thus you need to be able to prove that they could not have been
tampered with from when they are captured by the camera and when they
are stored. The other document you should look at is the House of
Lords Science and Technology Fifth Report it covers the use and
handling of Digital Photos as Evidence you can find a copy online
here (
http://tinyurl.com/am865).
As long as you take care and can show that you have a defined
handling procedure, that takes into account the guidance that is
available then in court if someone says to you how do you know it
hasn't been tampered with you go, here is our procedure, here are our
written logs all countersigned and witnessed...
> Second, how 'tamper-proof' does a computer log need to be to be
> considered
> trustworthy? I've seen terrabyte+ CD-based WORM drives, but would
> for instance
> burning logs to standard CD-R be considered fairly tamper-proof?
Having handled stuff for court before burning originals to CD is ok,
as long as you document on paper the procedure you undertook. Showing
Dates, Times and a description for each step in a book that you can
show that hasn't been tampered with for instance we had special A4
notebooks made which had 'hard' bindings that you could not add or
remove pages from with out it showing. You keep on book for one job,
always use pen, lines in the book you don't fill up with text you
draw a line through so nothing can be added and finally and most
importantly everything is witnessed, you always have a observer that
is watching you do what your doing and then countersigns the log book.
) but the complete lack of knowledge about most technical issues by the courts in todays world is quite frightening. I'm no conspiracy-nut either, I think in most things they try and do the right thing.
) I would have thought that you don't necessarily need the images as hard evidence in court as such, surely it will often fall into the category of circumstantial evidence which does not always need the same degree of verisimilitude.
