ISAC is pleased to announce the release of a new research report on state-level crime trends in Idaho during the COVID-19 pandemic.

The report, "Crime in Idaho During COVID-19: Time Series Analysis of Data from the Idaho Incident-Based Reporting System", utilizes interrupted time series analysis to identify changes in the frequency of reported crime during the earliest stages of the COVID-19 pandemic when Idaho's stay-at-home public health order was in effect. During that six-week period in March and April 2020, total crime and drug/alcohol crime was significantly lower than normal. The total number of criminal offenses during the stay-at-home order in 2020 was 28% lower than during the same period in 2019. However, that number rebounded to a normal level during the same six-week period in 2021, increasing 34% from the 2020 count. For drug/alcohol crime, the drop in 2020 was 45%, followed by a 97% increase in 2021. Counts of four other crime types (robbery, burglary, sexual violence, and intimate partner violence) did not experience significant changes during the stay-at-home order.

Similarly, total reported crime during the stay-at-home order decreased significantly in mostly urban and mostly rural counties (28% and 34% respectively), and subsequently rebounded to normal levels in the same six-week period in 2021. Although completely rural counties also experienced a 28% drop in crime during the same period in 2020, the drop was not statistically significant.

The results of this study provide valuable context for recent crime trends, particularly the disconnect between the sustained long-term decrease in total reported crime across the state that has continued for nearly 20 years and the public perception that crime spiked after the initial stages of the COVID-19 pandemic. Examining crime data on a weekly basis, as opposed to the more common annual analyses, illuminated effects of public policy on crime trends that would have otherwise gone unnoticed. These results also serve as a reminder that 2020 was not a normal year even in the criminal justice system, and comparisons between 2020 and any other year of data should be made with caution. Additionally, this study is one of the first in the nation to analyze data from the National Incident-Based Reporting System (NIBRS; the nation's flagship source for data on reported crimes) using interrupted time series analysis to explore how crime patterns at the state level change in response to a change in state policies. The success of this approach provides researchers with a new tool that can be used to identify and explain the impact of policy changes on crime trends in a wide range of contexts.

The full report is available online in the ISAC Publication Library (https://isp.idaho.gov/pgr/sac/library/).

The Idaho Statistical Analysis Center (ISAC) is located within the Planning, Grants & Research Department of the Idaho State Police. The mission of ISAC is to disseminate research, data and statistics related to crime, illegal drugs, victim services, and the administration of justice in Idaho. To learn more about ISAC, or to access other data dashboards and publications, visit our website at https://isp.idaho.gov/pgr/sac/.