The Government has argued that too much time has passed to allow a fair trial over alleged atrocities by British authorities in Kenya in the 1950s.
Guy Mansfield QC said the Foreign and Commonwealth Office faced "irredeemable difficulties" with witnesses and documents to defend the claim.
Without those witnesses, and indeed with the necessarily limited recollections of those who do survive, the very complicated and difficult task of determining the competing factual positions cannot be fairly conducted.
There is a dearth of evidence which can be given as to what was in people's minds when they made decisions and sent or read telegrams or attended meetings or were told of matters or visited places.
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Downpours keeping us on our toes today
The M20 in Kent has been closed in both directions after a pedestrian bridge allegedly collapsed on the motorway on Saturday.
The AA have warned of traffic jams and urged people to carry extra water in their vehicles because of the warm weather.