GPS Tracking Got Them

My friend owns a trucking business. Lately, he had noticed a rise in fuel consumption and cost. He investigated the matter and found out that some of his drivers have been using company vehicles for their personal errands. He wanted to have definite proof so he had all his vehicles installed with GPS tracking so he can monitor all the vehicle's locations. In just a matter of days, he was able to single out the drivers who have made unofficial trips. He confronted them and was able to impose the proper company sanctions against them. He was able to arrest the situation before it got worse.