The aim of the project is to develop, deploy and evaluate a decision support system for vehicle control officers. Avoiding the inconvenience for compliant vehicles to be stopped and delayed, and redirecting the attention to the non-compliant actors is a challenging task. This paper describes the use of Weigh-in-motion systems (WIM) to select overweight vehicles; as well as a literature review showing an absence of best practice consensus relative to the use of WIM data for evaluating the overall impact of removing overloaded trucks from the roads. Methods related to the evaluation of the potential impacts of WIM systems are discussed in the paper. Three WIM systems were tested and compared with the static weight control. They had different reliability and accuracy and this have implications on the errors that must be minimized in order to use WIM for selection of probable overweight vehicles: false negatives and false positives. A model was developed to study these effects.