One study compared accident reports done by police to those done by hospital emergency rooms. Furthermore, Rothe argued that police handle their investigations of accidents in an automatic fashion. Another problem with obtaining all vital statistics and information from police is that they have other duties to handle other than traffic accidents. In certain areas of the United States police try to handle reports quickly in order to better serve the public. The problem is that trying to rush through reports can allow for details to be overlooked.
Many experts claim that speed is a major factor that contributes to accidents.
Rothe argues against this idea. He says that many other confounding variables are in conjunction with speed. In order for speed to be confirmed as the ultimate causal factor of accidents, all other factors would need to remain constant. Weather conditions, traffic flow, drivers' moods, etc. would all have to remain exactly the same as speed is manipulated. Car size was also something that Rothe mentioned.