Usability on patrol

The introduction of computers into police patrol cars comes with an increase in driver distraction issues. We will describe the usability process and techniques we adapted to study computers in law enforcement patrol cars. Our approach to assess the risk of driver distraction in the police vehicles was a combination of a National Highway Traffic Safety Administration (NHTSA) workload assessment protocol and cognitive modeling. This combination proved useful without the high cost of driving simulators and instrumented test subjects. Using cognitive modeling, we could identify the potential problems for certain tasks. For example, we found that automating the task of running a license plate with a typical mouse-keyboard interface, could increase the workload by more than seven hundred percent compared with doing the same task via radio contact with dispatcher. We also found measuring by glances instead of time to be a useful technique in practice.