Public Policy Institute of California: Decline in Statewide Arrest Rate Driven by Lower Crime Rates and Criminal Justice Reforms

SAN FRANCISCO — The overall arrest rate in California has dropped substantially since 1980. Yet there is wide variation in rates at the county level, with recent arrest rates highest in counties with poor economic conditions and lower levels of educational attainment. An examination of county arrest rates also shows that the greatest disparities in arrests between African Americans and whites are in relatively well-off counties.

These are among the key findings of a report released today by the Public Policy Institute of California (PPIC).

Between 1980 and 2016, the arrest rate in California declined substantially, reaching a historic low of around 3,400 arrests per 100,000 residents. This decrease is largely attributable to a parallel decline in the statewide crime rate. An analysis of county-level arrest rates in recent years — from 2014 to 2016 — finds that local crime rates largely account for differences in arrests across counties and also shows other factors that are associated with higher rates. Counties with the highest arrest rates tend to have the lowest average annual earnings and the highest levels of poverty. In addition, high-arrest counties tend to have higher unemployment and lower college graduation rates.

County arrest data also show that disparities between the arrest rates for African Americans and whites — while substantial in most California counties — vary widely and are greatest in counties that tend to be better off economically. The disparities between arrest rates for African Americans and whites are higher in counties that are more affluent (as evidenced by higher incomes and lower poverty rates) and have more college graduates. In counties with the highest racial disparities in arrests, the African American arrest rate is about six times higher than the white arrest rate, compared to almost double among counties with relatively low racial disparity.

“A variety of factors are linked to whether or not a county has a high rate of arrests,” said Magnus Lofstrom, policy director and senior fellow at PPIC and an author of the report. ​“Law enforcement practices play a role, of course, but our findings highlight how specific facets of the community environment are associated with higher arrest rates.”

The report is based on arrest data from 1980 to 2016, a period of major changes in state and federal criminal justice laws, with the examination of county arrest trends focusing on 2014 to 2016. The analysis is based on arrests and citations reported monthly by law enforcement agencies to the California Department of Justice’s Criminal Justice Statistics Center.

The report also finds:

• The statewide arrest rate declined in the aftermath of two key criminal justice reforms: public safety realignment and Proposition 47. Driven by drops in misdemeanor traffic and alcohol-related arrests, the statewide arrest rate decreased by about 7 percent (a decline of slightly more than 300 arrests per 100,000 residents) after public safety realignment in 2011, which shifted responsibility for many non-serious, non-violent, and non-sexual offenders from the state to counties. The arrest rate went down by another 11 percent (440 arrests per 100,000 residents) after voters passed Proposition 47 in November 2014, driven by declines in felony arrests, especially for drug offenses. Prop 47 reclassified a number of drug and property felonies as misdemeanors.
• Variation in local crime rates largely accounts for differences in arrest rates across counties. Arrest rates vary widely across California counties. Counties with the highest rates arrest two to three times as many suspects per 100,000 residents as do those with the lowest rates. About three-fourths of this variation can be explained by differences in crime rates, though there are a number of other contributing factors.
• Smaller, rural counties tend to have higher arrest rates. High-arrest counties in California have lower population density than other counties. Counties with the lowest arrest rates have an average of about 2,000 residents per square mile, while counties with the highest arrest rates have an average of fewer than 50 residents per square mile.
• The ratio of law enforcement officers to residents does not appear to affect arrest rates. County arrest data suggest that differences in county arrest rates are not driven by the number of law enforcement officers per 100,000 residents.

The report, Key Factors in Arrest Trends and Differences in California’s Counties, is supported by Arnold Ventures. In addition to Lofstrom, coauthors are PPIC researchers Brandon Martin, Justin Goss, and Joseph Hayes, as well as Steven Raphael, professor of public policy at the University of California, Berkeley.

About PPIC

The Public Policy Institute of California is dedicated to informing and improving public policy in California through independent, objective, nonpartisan research. We are a public charity. We do not take or support positions on any ballot measure or on any local, state, or federal legislation, nor do we endorse, support, or oppose any political parties or candidates for public office. Research publications reflect the views of the authors and do not necessarily reflect the views of our funders or of the staff, officers, advisory councils, or board of directors of the Public Policy Institute of California.