*This report has been updated to include charts.
COLUMBIA — Across the state, African-American drivers are more likely than white drivers to be pulled over, according to an attorney general's report.
The highest number of traffic stops by Columbia police occur in the First Ward, almost double the number in the next highest ward, the Missourian reported last year.
The report on ethnic and racial profiling during traffic stops, released Friday by Attorney General Chris Koster's office, said that African-Americans are more than two times overrepresented in traffic stops by the Columbia Police Department and Boone County Sheriff's Department and nine times overrepresented in stops by Ashland police.
Each year, the report calculates a racial disparity index, which shows the likelihood that a certain racial or ethnic group will be stopped by the police compared to the group's proportion of the local population. Values of more than one indicate overrepresentation, and values of less than one show underrepresentation.
In the case of Columbia police, approximately 22.8 percent of 18,414 traffic stops in 2013 involved African-American drivers, who make up 9.96 percent of the population. The percentage of African-Americans stopped in Columbia divided by their representation in the local population results in a disparity index number of 2.29, slightly up from 2.26 in 2012.
The Boone County Sheriff's Department had a disparity index of 3.03 for 2013, up from 2.51 in 2012, which marks the third consecutive year its index has risen.
The Ashland Police Department had a disparity index for African-Americans of 9.54 in 2013, down from 14.94 last year and 31.52 in 2009. African-Americans make up 0.66 percent of the local population in its jurisdiction.
The MU Police Department's report did not include disparity index statistics because its jurisdiction does not have applicable population numbers, but the department's search and arrest rates for African-Americans were higher than those of whites in the 2013 report.
The statewide picture was just as suggestive of racial bias in traffic stops, as the report found that black drivers were 66 percent more likely than white drivers to be stopped based on their proportionate share of the driving-age population last year.
In 2013, the statewide African-American disparity index was 1.59, a slight increase from the 2012 rate of 1.57, Koster said in a written statement Friday.
The 2013 report marked the 11th time in 14 years that the disparity index for African-American drivers has increased.
The disparity is up significantly since 2000 when the state began reporting racial demographics about traffic stops. In 2000, black drivers were 30 percent more likely than white drivers to be pulled over.
"This suggests a disturbing trend, and I hope communities with similar findings will make a serious effort to identify the causes," Koster said.
He cautioned that the statistics don't prove that law officers are making vehicle stops based on the race of the driver.
The report is based on a review of nearly 1.7 million traffic stops made by officers for 613 law enforcement agencies in 2013. It compares the traffic-stop data to the racial composition of the population in each jurisdiction and to the state as a whole.
Law enforcement officers have said racial disparities in traffic stops might appear higher in some cities that are made up of predominantly white residents and that have interstate highways or retail and tourist destinations. That's because the cities might attract minority drivers at a higher proportion than the local population.
The report shows that Hispanic drivers were stopped at a lower proportional rate than white or black drivers. Law officers searched Hispanic and black drivers at a higher rate than white drivers. But of those who were searched, whites were found with contraband at a higher rate than black and Hispanic drivers.
Missouri law requires law enforcement agencies to report their annual traffic-stop data to the attorney general's office, which must produce a report by June 1. For its analysis, the attorney general's office relied on criminal justice professors at Arizona State University, the University of Missouri-St. Louis and the University of South Carolina.
This article includes reporting by David A. Lieb of The Associated Press.
Supervising editor is Katherine Reed.