Analysis of an LAPD report documenting traffic stop data between July 1, 2002, and November 30, 2002 reveals that 99% of drivers stopped by police in Los Angeles consented to officers' search requests. The report shows that 7.4% of African American drivers and 5.3% of Hispanic drivers were asked to consent to a search, while only 1.5% of white drivers were asked for consent to search.
Source: "POSTING MOTOR VEHICLE AND PEDESTRIAN STOP DATA" Los Angeles Police Department, 2002
The following statistics come from the US Department of Justice, Bureau of Justice Statistics report, Contacts between Police and the Public (February, 2001):
An estimated 43.8 million people 16 years or older—or about 21 percent of the population that age—had at least one face-to-face contact with the police during 1999. About 52 percent of these interactions were during traffic stops (page 2).
About 19.3 million drivers, or about 10.3 percent of licensed drivers, were pulled over by police. Among those pulled over, about 1.3 million motorists said they or their vehicle had been searched. And in almost 90% of those searches, police found no evidence of criminal wrongdoing (page 2).
Of the 1.3 million searches of motorist, the likelihood of police finding criminal evidence was not significantly different between the 845,000 searches without consent (12.9%) and the 427,000 searches with consent (14.2%) (page 21).
During a traffic stop, police were nearly twice as likely to carry out some type of search on an African-American (11.0%) or Hispanic (11.3%) than a white motorist (5.4%) (page 20).
Searches of white drivers of their vehicles were twice as likely to find criminal evidence (17%) than searches of black drivers (8%) (page 22).
Persons age 18 to 19 had a per capita rate of contact arising from a motor vehicle stop of 225 per 1,000, which is more than 4 times the rate of traffic stops experienced by those ages 50 or older (page 1).