Since 2008, using a handheld communication device while driving has been prohibited by state law in California. The University of California, San Diego, in a traffic safety study, surveyed 5,000 college students between 18 and 29 years old in San Diego County, and the study found that approximately 78 percent of those surveyed reported using a handheld communication device while behind the wheel of a moving automobile despite the law. Half of the survey respondents said they will send and receive text based messaging while driving on the freeway, 60 percent of the respondents reported sending text messages in slow moving traffic, and 87 percent reported sending text messages at traffic signals.
The California Office of Traffic Safety released a study stating that of the drivers observed at 130 different intersections across 17 counties in the state of California at various times of day, 11 percent of the were engaging in mobile phone related distracted driving practices. This marks a rise of four percent from the results of a similar study prepared in 2011. Drivers aged 16 to 25 years old marked the biggest increase in handheld communication use behind the wheel. Twice the number of drivers in this age group were observed using mobile phones while driving. This is an increase from 9 percent in 2011 to 18 percent this year. Safety experts hypothesize the increase might be caused by a rise in the rate of smart phone use by drivers in the youngest demographic.