Analyzing Traffic Stop Data From 2017
Story by the Connecticut Data Collaborative
May 2018
In 2017, there were 542,820 traffic stops conducted in Connecticut by local and state police.
While the total number of stops has been slowly declining every year since 2014, the trend varied for drivers of different races and Hispanic ethnicity. In 2017, there were more stops for Black non-Hispanic, Hispanic (of all races), and American Indian / Alaska Natives non-Hispanic drivers compared to 2016.
Police reports differentiate over a dozen reasons for stop: speed related, stop signal, seatbelt, cellphone, etc. Below is the bar chart representing percentage distribution of stop reasons for each race. We can see that speed-related, moving violation, and registration are the three most common reasons for stops.
There are several outcomes to a traffic stop. Let's look at three of them — ticket, written and verbal warnings — and see if drivers of various races get them with similar frequencies. The chart below shows the percentage of each of the three outcomes and does not account for other dispositions (such as arrest or summons).
The share of tickets among three possible outcomes is nearly the same for White non-Hispanic (45%) and Black non-Hispanic (44%) drivers. Black non-Hispanic drivers have the highest share of Verbal warnings (45%) and the lowest share of Written warnings (11%, same for Hispanic drivers). American Indian / Alaska Native non-Hispanic drivers have the highest percentage of stops resulting in a ticket, 58%.
17,536 cars were searched in 2017. As a result of the search, contraband was found in 6,410 cases. White non-Hispanic drivers had both the largest number of stops where contraband was found (3,175), as well as the highest contraband-to-car-search ratio, with 42% of searches resulting in found contraband. Black non-Hispanic and Hispanic drivers had the lowest percentages (33% and 32%, respectively).
The four graphs below show the total numbers of cars searched and contraband found for each race and Hispanic ethnicity for 2014–2017.