The difference between diagrams and a model is the model has three dimensions. Cars, trees, poles, signs, buildings and people can all be included. If the vehicles are not fixed on the model board, they can be moved and placed by witnesses to demonstrate what happened. Scale models can be as simple or intricate as desired. They are particularly useful for situations involving vehicles that move in several directions, such as backing up then moving forward, before an accident occurs.
Scale models are more expensive than diagrams but have the advantage of depth.
The production of a scale model can be moderate to expensive. The cost is dependent entirely upon the size of the scene to be presented and the number of items that will be shown. Costs can increase if the model is to have any moving parts or lighting installed. Scale models tend to be fairly delicate so care must be taken in handling and shipping should be held to a minimum. Video animations are a new trend in litigation and still expensive.