WWW Liability (slightly off-topic, but someone might know)

[Ian G Batten]

The following claim has been made in support of the purchase of a
product:

  As far as the UK is concerned we believe that UK
  government can make the company liable in case
  an employee (using his companie's infrastructure)
  accesses e.g.: a terroristic site and does bad
  things based on this...(it seems not to be
  enough to simply provide a company policy that
  forbids the use of such web sites).
  So it is "recommended" to pro-actively prevent
  the use of illegal (and non-work-related) web sites
  using such a tool.

Has anyone heard this particular meme before?  Does it have any basis in
fact?  My money's on ``Yes, from a salesman'' and ``No'', but I'd be
interested to hear other answers...

ian