Telematics systems frequently find a place in legal cases. A Telematics Device tracks vehicle movements, generally using GNSS. It records movements and an array of other data which is usually relayed to a remote data centre that may be operated by/for a fleet management or insurance company.
The data may be used to prove that a vehicle (and by implication its driver) was at a particular place at a particular time, the routes it travelled, and its speed and other driving characteristics.
At its best Telematics provides a reliable set of "spy" data that proves matters beyond reasonable doubt. At its worst, the operating company turns out to be evasive, withholding data or even pretending that the original digital format doesn't exist, even when faced with a Court order. Imagine being delivered two boxes of paper readouts comprising more than 1600 pages of numbers that showed time, location, speed, distance travelled, heading, gear selected, acceleration, ... . Could I explain the vehicle movements during the past month?