The Official Smallprint :-
From the First Installation Date, we will use the In-Car Device to capture data from your vehicle relating to the date, time, speed, location and direction of travel.
We, and those acting on our behalf, will use the data captured by the In-Car Device for the purposes of:
1. Calculating and charging insurance premiums based upon actual vehicle usage;
2. Disclosing your personal data to Smartnav who as our supplier of the In-Car Device will separately control your personal data for the purpose of providing you with the Accident, Emergency and Breakdown Service .... etc
Their obligations under the Data Protection Act 1998 :-
If approached, we shall only provide information about you to those legally entitled to it, and where we are obliged to release it.
So, although your Journey Speed is not specified anywhere on the monthly bill, & you are not charged at a higher rate if you ever exceeded the speed limit on a particular road, I would think it possible the insurance company may analyse your speed data just prior to any accident you may be claiming on.
{But not sure if in doing so they would be in breach of DP act ... Interesting point}
Information is also
anonymously passed on to Trafficmaster for Vehicle flow analysis.
Trafficmaster incidentlly, will be using data from drivers mobile phones to monitor traffic flow & pass that data back to others to help them avoid holdups & accidents.
See >>
Now there’s no need to be spooked by phantom jams - Times Online
So, even if you havnt got one of these devices fitted, anyones movements can be checked on if neccessary, by way of your mobiles standby signal.
And for anyone who isn`t paranoid yet:-
"Trafficmaster relies on data from some 7,500 roadside cameras and sensors fixed to bridges, which monitor traffic speed then send out alerts whenever it drops below 30mph"
This data is also recorded & can be requested by the relevant authorities, as has been witnessed many times in non-speeding related court cases - such as to provide or disprove alibi`s in murder enquiries etc.