Notable new research on modern operation and impact of Three Strikes law in California

I just came across this notable new report from the California Policy Lab released a couple of months ago titled simply "Three Strikes in California." Here is the 45-page report's listing of "Key Findings" (with bolding in the original):

• Three-Strikes enhancements affect a large share of the currently incarcerated prison population, but a smaller share of admissions to prison.  Less than one-third of prison admissions since 2015 involve a strike enhancement, with most receiving a doubled-sentence enhancement and a smaller percentage receiving a third-strike enhancement. At a given point in time however, individuals with strike enhancements constitute a larger proportion of the incarcerated population because they serve longer sentences

• Nearly 65% of admissions to prison with a doubled-sentence enhancement are for a non-violent, non-serious offense.

• Given the longer sentences imposed for serious or violent offenses, the reverse is true for people currently incarcerated: approximately 71% of those with doubled-sentence enhancements were convicted of a serious or violent offense.

• Black individuals are heavily over-represented among people serving sentences with third-strike enhancements, and to a lesser degree, with doubled-sentence enhancements. Overrepresentation exists relative to the racial/ ethnic composition of the prison population, and overwhelmingly relative to the racial/ethnic composition of the resident population of California.

• Judicial and prosecutorial discretion can mitigate the severity of strike enhancements.  The data suggests that judges and prosecutors may mitigate the severity of doubled-sentence enhancements by choosing (or accepting) lower sentence length options, but the effect of discretion on overall sentence length is modest.

• The use of strike enhancements varies widely across counties.  While third-strike sentences are considerably more rare today than in past years and the ordering across counties has changed over time, high-use and low-use counties documented in the early 2000s are largely similar in terms of rank today.

• The implementation of Three Strikes does not explain statewide declines in crime over time.  Early evaluations claiming large impacts on crime fail to account for national crime trends and also suffer from methodological flaws. More recent research suggests that Three Strikes may have a modest deterrent effect on relatively less serious crime, but likely does not account for the declines in California’s crime rates beginning in the mid-1990s.  Crime fell contemporaneously throughout the nation, and comparisons of crime trends in California to states that did not pass Three-Strikes laws reveal very similar trends over the subsequent two decades.