How the data works.
Here’s how LA Crime turns four different police data sources into one interactive research tool.
Official sources
The live site reads public records from the Los Angeles Police Department, Los Angeles County Sheriff’s Department, Long Beach Police Department, and Santa Monica Police Department. Santa Monica moved from its old open-data page to a new ArcGIS Community Crime Dashboard; LA Crime now reads the current NIBRS layer behind that application. The County Sheriff’s separate dashboard provides another check on its latest published date.
Why agency totals stay separate
Los Angeles, Long Beach, and Santa Monica publish one record for each offense, while the County Sheriff publishes incident records. Because those are different counting methods, LA Crime does not add them into one misleading county total. Percent changes compare an agency only with its own earlier period. Case totals count each case number once, while offense totals keep every offense attached to that case.
Crime-name translation
Every record keeps the agency’s original wording. LA Crime also translates abbreviations such as TFMV into “Theft from a motor vehicle” and groups related descriptions under familiar names such as assault, burglary, vehicle theft, theft from a vehicle, and vandalism. Unclear descriptions stay in “Other” instead of being guessed.
Dates and late reports
Impossible and future dates are removed before a time period is chosen. Some incidents are reported days after they happen, so Los Angeles trend comparisons stop before the newest incident date. That keeps late-arriving reports from making the newest period look artificially low. Today can remain visible while new records arrive, but it is left out of the comparison. Older archives keep their original latest date and stay out of the default Current view.
How much data is loaded
The county page shows how many records are available for charts, maps, and details. If an agency returns more detail than the site can load at once, the page shows both the loaded number and the full available number. A dash in the crime-group table means no loaded description matched that group; it does not prove that no incident occurred.
Neighborhoods and map locations
Los Angeles Police coordinates are matched to familiar neighborhood boundaries from the Los Angeles Times Mapping L.A. project. Police service areas remain separate under their own pages, and independent cities use their own police agencies. Map dots use the public coordinates supplied by an agency and point to a block or approximate location—not an exact building or person. County Sheriff and Long Beach records remain in charts even when they do not include usable map coordinates.
Population density and crime rates
The neighborhood comparison uses the U.S. Census Bureau’s 2024 five-year population estimate. Census areas are matched to the familiar neighborhood that contains their center point, then their population estimates are added together. This is approximate because Census and neighborhood boundaries do not always line up. The comparison includes neighborhoods with enough Census matches and at least 2,000 estimated residents. Visitors, commuters, land use, reporting behavior, and policing can all affect the pattern, so the chart shows a relationship—not a cause or a personal-risk score.
Which time is shown
Los Angeles Police, the County Sheriff, and Santa Monica charts use the time an incident happened. Long Beach uses the report time because it does not publish the incident time. Missing times stay marked unavailable rather than being treated as midnight.
Updates and missing data
The site checks for updated records every hour; city and neighborhood pages refresh every 15 minutes. Source responses must pass checks for the expected fields, usable records, valid dates, and future dates before they appear. Santa Monica’s ArcGIS layer is paged so the complete comparison period is loaded even when it exceeds the service’s single-request limit. If an agency source fails its checks, it is marked unavailable. The site never invents replacement records.