每年秋季, the Federal Bureau of Investigation aggregates and distributes annual crime data from law enforcement agencies across the country. Many agencies now post their own weekly and monthly data online, 允许研究人员, including those at the bet9登录页面 (CCJ), 以接近实时的方式分析和报告趋势.
9月27日，联邦调查局 发布 2020年年终报告. 政府的数据很大程度上反映了什么 CCJ和Arnold Ventures在1月份发布了报告 基于34个城市的样本. 这两份报告, 例如, indicated that in 2020 homicide increased by nearly 30% over the year before.
This brief summarizes key takeaways based on the newly issued FBI report as well as historical and more recent data. All data used in this report are retrieved from the FBI’s Crime Data Explorer 网站，除非另有说明.
- Violent crime, particularly homicide, increased in 2020. 的 increase has slowed in 2021 and levels remain below historical highs. 暴力犯罪率上升了4倍.6%，而凶杀率上升了28.9%，这是历史性的一年增长.1 财产犯罪率下降了8.1%. 根据 CCJ收集的数据, homicides in a cross-section of cities continued to rise through the first half of 2021 but at a slower rate of 16%. 的 rate of increase slowed between the first (up 23%) and second (up 11%) quarters of the year. 尽管2020年一些犯罪行为有所增加, rates for all offenses remain below the peaks of the early 1990s. 的 2020 homicide rate is 33% lower than its most recent peak in 1991, while the property crime rate is 61% lower than its peak that year. 的 violent crime rate is 47% lower than it was at its most recent peak in 1991, but is at roughly the same level as the last increase in 2016.
暴力犯罪率，1979 - 2020年
谋杀率，1979 - 2020年
1979 - 2020年财产犯罪率
- A greater share of homicides involved firearms in 2020. 的 percentage of homicides involving firearms has been increasing steadily over time, reaching a peak of 77% in 2020 compared to 73% in 2019.
涉及火器的凶杀案，2010 - 2020年
3. 的 age of homicide victims and offenders remains relatively stable, 尽管在2020年略有下降. Media reports have highlighted tragically young victims of violence over the past year, but the age of homicide victims and perpetrators remained largely the same. Victims 19 and younger comprised 17% of homicide victims in 2010; they were 15% of victims in 2020. 类似的, the share of people arrested for homicide who were 19 and younger decreased from 20% to 18% from 2010 to 2020. 与此形成鲜明对比的是, the percentage of offenders and victims aged 30 to 39 has been steadily increasing over the past decade.2
罪犯年龄，2010 - 2020年
2010 - 2020年凶杀受害者的年龄
- 的 percentage of Hispanic victims and offenders has decreased. 的 racial and ethnic composition of homicide victims and offenders has changed since 2010. 黑人受害者的比例增加了6%, while the percentage of White and Hispanic victims has decreased, 分别下降6%和9%. 的 percentage of White and Black offenders remained consistent over the 10-year period. 的 proportion of offenders who are Hispanic fell from 20% in 2010 to 9% in 2020.3
2010 - 2020年凶杀受害者的种族和民族
罪犯的种族和民族，2010 - 2020年
- 的 2020年凶杀清除率显著下降, 延续了从20世纪70年代开始的下降趋势. 1976年凶杀案的破案率是82%.4 In 2019, the rate was 55% and by 2020 it had fallen still further, to 50%. This 5% decrease is the largest decrease in clearance rates since 1989.5
2010 - 2020年凶杀清除率
- 的 circumstances of homicides have grown increasingly unclear. While the absolute number of homicides is known with confidence, the relationships between victims and offenders and the motives behind the killings have become less clear over time. When fewer cases are solved, authorities know less about them. In 2020, 52% of homicide relationships were classified as “unknown,” up from 44% in 2010. 的 share of unknown homicide circumstances rose from 46% to 56% over the same period. 一些媒体报道, and some elected officials and candidates for elected office, have suggested that homicides have become more random and brazen. 的 gaps in the national data prevent an overall statistical assessment of those characterizations.
被害人-罪犯关系，2010 - 2020
凶杀情节，2010 - 2020
注意: This brief utilizes the definitions and labels of the FBI Uniform Crime Reporting Program dataset. 的 Council is committed to using person-first language in its reports, 三角裤, and data analyses and has done so when possible within the confines of this dataset.
- 凶杀案增加了29起.2020年将比2019年增加4%.
- 的 age of the offender could not be determined by police in approximately 32% of homicide cases between 2010 and 2020.
- Race and ethnicity measures should be interpreted with caution. Because not all agencies report detailed offense information every year, fluctuations can be the result of reporting and not actual changes. 亚洲, 美国印第安人或阿拉斯加本地人, and native Hawaiian are not reported due to the concern of reporting inconsistency. 的 race of the offender could not be determined by police in approximately 29% of cases between 2010 to 2020.
- This rate was generated by analyzing a sample of 154 large cities. 看到:Mancik,. M., & 帕克,K. F. (2019). Homicide clearances during pre-and post-US crime drop eras: 的 role of structural predictors and demographic shifts, 1976–2015. 犯罪与正义杂志, 42(3), 237-256.
- 得到和计算的数据: http://www.openicpsr.org/openicpsr/project/100707/version/V17/view. Clearance rates were calculated by dividing the total number of cleared murders by the total number of murders. This figure does not adjust for murder clearances that may have occurred during a prior year.