Caltrans officials reported that between July 2002 and 2012, nine people were killed and 64 injured in wrong-way collisions that occurred on state highways in Santa Barbara County. Of those collisions, 37 occurred on Highway 101. According to Caltrans spokesperson Jim Shivers, 58.7 percent of these wrong-way collisions involved drivers operating their vehicle under the influence, and 80 percent took place after dark. Shivers said Caltrans explored the possibility of installing directional spike strips on freeway on-ramps but decided against it. Spike strips are effective in deflating only slow-moving vehicles, and engineers concluded that the sight of spike strips could cause motorists traveling the right way to slam on their brakes in response to an apparent obstacle on the road.