There is this criminal trial going on in Stockholm concerning a group of suspects that entered a bank vault through the roof over a weekend in 1992. They have been prime suspects for a long time but evidently it has taken a lot of time to build up a case against them. Traffic analysis (but not tapping of the actual conversations, GSM? - no mention of the system in the news stories) plays a substantial role in the prosecution. 'A and B were at X at the same time','B and C were in the vicinity of the Bank at this time' etc. The suspects have not tried to argue that their cellulars were on loan to some stray persons. We all know that a booted cellular is a wonderful Area Locator. (I wonder if the suspects new?) But I have (naively) been thinking that the authorities needed prior suspicion using this feature in 'real time'. Judging from what has been written about this trial the police must have requested, and received, logged traffic data quite some time afterwards. Perhaps they log it for ever? Mats