"In 2011, less than 1% of the 241.4 million U.S. residents age 16 or older were involved in a street stop during their most recent contact with police (table 1; appendix table 2). A greater percentage of males (1%) than females (less than 1%) were involved in street stops during 2011. Persons ages 16 to 24 were more likely than persons age 35 or older to be involved in street stops. While no differences were observed in the percentage of non-Hispanic white, non-Hispanic black, and Hispanic populations age 16 or older involved in a street stop, among those who were stopped, a smaller percentage of blacks (38%) than Hispanics (63%) or whites (78%) felt the police behaved properly during the stop.

"Traffic stops were a more common form of police contact than street stops in 2011. About 10% of the 212.3 million U.S. drivers age 16 or older were stopped while operating a motor vehicle during their most recent contact with police.1 As with street stops, a greater percentage of male drivers (12%) than female drivers (8%) were pulled over in traffic stops. Across age groups, the highest percentage of stopped drivers was among drivers ages 18 to 24 (18%). A higher percentage of black drivers (13%) than white (10%) and Hispanic (10%) drivers age 16 or older were pulled over in a traffic stop during their most recent contact with police.

"A higher percentage of drivers in traffic stops (88%) than persons involved in street stops (71%) believed the police behaved properly during the stop. White drivers pulled over by police (89%) were more likely than black drivers (83%) to think that the police behaved properly, while no difference was observed between the percentages of stopped white drivers and Hispanic drivers who thought that the police behaved properly. There was also no statistical difference in the percentages of black and Hispanic stopped drivers who believed the police behaved properly."

Source

Lynn Langton, PhD, and Matthew Durose, "Police Behavior During Traffic and Street Stops, 2011" (Washington, DC: Bureau of Justice Statistics, Sept. 2013), NCJ242937.