Anonymity of prepaid phone chip-cards

[ken]

Thomas Shaddack wrote:

[...]

> Suggested countermeasure: When true anonymity is requested, use the card
> ONLY ONCE, then destroy it. Makes the calls rather expensive, but less
> risky. Make sure you can't be traced back by other means, ranging from
> surveillance cameras in the vicinity of the phone booths to the location
> data from cellphones (because, as it's well-known but often overlooked,
> the cellphone networks know the location of every active phone).

In local pubs round where I live it is not at all uncommon to find 
people buying & selling SIM cards, swapping them, or just handing 
roudn to friends & family members.

If these persons are involved in activities which would be 
disapproved of by the law, I imagine that they would be very 
unlikley to be anything that could be called terrorism. More 
likely doing casual work without paying tax,  using drugs 
deprecated by governments, trading in unauthorised DVDs, perhaps 
employing illegal immigrants. (Allegedly that is  - as far as I am 
aware the apparently oriental gentleman who walks round pubs and 
clubs late at night offering DVDs and CDs for a pound is in full 
complience with all local copyright laws)

There was a notorious murder locally (Damilola Taylor) which the 
police took a logn time to charge anywone for. When they finally 
got round to it, some of the evidence turned on mobile phone 
records. One piece could not be used, because the court was 
satisfied that the family and friends of the accused persons 
swapped and shared phones so frequently that there was no way to 
connect the use of a phone with an individual.