What is interception?

[Charles Lindsey]

I have been looking at the NTL Judgment
<http://www.courtservice.gov.uk/judgmentsfiles/j1293/NTL.htm> in the
light of our recent discussions. It raises some intresting points.

Section 2 defines the meaning of "interception". Subsection (2)
provides: "For the purposes of this Act, but subject to the following
provisions of this section, a person intercepts a communication in the
course of its transmission by means of a telecommunication system if,
and only if, he --
    (a) so modifies or interferes with the system, or its operation, or=20
    (b) so monitors transmissions made by means of the system, as
to make some or all of the contents of the communication available,
while being transmitted, to a person other than the sender or intended
recipient of the communication."

"Ifsubsection (2) ended there, the problems to which this case gives
rise would not exist because subsection (2) only applies, first of all,
to communications in the course of transmission; and secondly, to make
some or all of the contents of the communication available while being
transmitted to a person other than the sender or intended recipient of
the communication."

This does comply with my contention that making it available to a
"person" is critical. However, it also draws attention to the "while
being transmitted" condition. Moreover, 2(7) makes it clear that it is
still "being transmitted" until the intended recipient has collected it
from the POP mailbox.

Which raises an interesting possibility. Suppose the operator of a
telecommunications system wishes to see Alice's mail (perhaps he is
Alice's employer, and the telecommunications system is the office
intranet).

So he waits until Alice has retrieved her mail and then, within the next
microsecond, grabs it from her mailbox before it gets deleted, or scours
his caches or swap spaces where he will likely still find it. Then,
apparently, he has not committed any offence !!!!!!!


The next issue is 2(8):

"For the purposes of this section the cases in which any contents of a
communication are to be taken to be made available to a person while
being transmitted shall include any case in which any of the contents of
the communication, while being transmitted, are diverted or recorded so
as to be available to the person subsequently."

And that is certainly "quarantine". There was no suggestion that the
mere fact it was on their machine and therefore accessible by anyone
with root privilege was of relevance (as Peter has been maintaining).
They seemed to be satisfied that it was the person for whom the
quarantined copy was made that was relevant.

In this case, it was quarantined to be accessed later by the Police, in
the event that the Judge actually made the order for it to be disclosed
(in the absence of such an order, it would presumably be destroyed).
The court held that that did indeed constitute "interception" (slightly
surprising, since I would have thought it could not have been considered
"available" until the Judge had actually made his order, but that aspect
does not seem to have been considered).

But, that then being interception, NTL still lost the case on the
grounds that the interception was lawful because it was in exercise of a
statutory power arising under PACE.

However, on the strength of what was reported, I would suppose that
communications quarantined with the intent that only the intended
recipient could recover them (or give instructions for them to be
examined/destroyed/whatever) would not be considered as interceptions,
much less communications that were discarded unread.


Charles H. Lindsey ---------At Home, doing my own thing--------------------=
----
Tel: +44 161 436 6131 Fax: +44 161 436 6133   Web: http://www.cs.man.ac.uk/=
~chl
Email: chl@clw.cs.man.ac.uk      Snail: 5 Clerewood Ave, CHEADLE, SK8 3JU, =
U.K.
PGP: 2C15F1A9      Fingerprint: 73 6D C2 51 93 A0 01 E7 65 E8 64 7E 14 A4 A=
B A5