ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · CHICAGO, IL · DECEMBER 2024
Purpose: Machine-readable JSON endpoint for AI agents, LLMs, researchers, and programmatic consumers. Returns all underlying crash data and AI-generated commentary without HTML.
Authentication: None required. Public endpoint.
GET: https://thatcarhitme.com/api/crash-data/reports/data/illinois/chicago/december-2024-report
Monthly Traffic Safety Analysis
8,788 CRASHES IN
CHICAGO, IL
DECEMBER 2024
In December 2024, Chicago experienced 8,788 total crashes, a decrease of 3.56% compared to the 9,113 crashes recorded in December 2023. The most notable year-over-year shift was a significant reduction in total fatalities, which decreased by 53.85% from 13 in the prior period to 6 in the current period. Total injuries also saw a decrease of 3.99%, from 1,951 to 1,873.
8,788
▼ -3.6%was 9,113
Total Crash Events
6
▼ -53.8%was 13
Persons Killed
1,873
▼ -4.0%was 1,951
Persons Injured
2,597
▼ -9.2%was 2,861
Hit-and-Run Crashes
Note: "Persons Killed" (6) counts individual fatalities across all crash events. "Fatal" in the severity table below (5) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 15 crashes with unreported severity are not shown in the severity breakdown.
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Aggregate counts from crash, person, and vehicle records
Trend Summary
Overall, crash data for December 2024 indicates a downward trend in traffic incidents compared to the previous year. Total crashes decreased by 3.56%, from 9,113 to 8,788. This reduction was accompanied by a substantial 53.85% decrease in total fatalities.
2,597
Hit-and-Run Crashes — December 2024
▼ -9.2% vs prior (2,861)
Hit-and-run crashes decreased from 2,861 in December 2023 to 2,597 in December 2024, representing a reduction of 264 incidents. The hit-and-run rate also decreased, moving from 31.4% of total crashes in the prior period to 29.6% in the current period, indicating a downward trend.
Vulnerable Road User Casualties
1
Pedestrians Killed
0
Cyclists Killed
5
Motorists Killed
0
Other Killed
225
Pedestrians Injured
66
Cyclists Injured
1,576
Motorists Injured
6
Other Injured
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Mode classified from person records (driver/passenger → motorist; pedestrian; bicyclist → cyclist; in-line skater / unspecified → other)
When Crashes Happen
The peak day for crashes remained Friday in both periods, though the count decreased from 1,870 in December 2023 to 1,400 in December 2024. The peak hour for crashes also remained consistent at 5 PM, with a reduction from 771 crashes in the prior period to 711 crashes in the current period. Crashes on Monday increased from 1,008 to 1,391, while crashes on Saturday decreased from 1,571 to 1,171.
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Crash date field aggregated by weekday
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
The fatal crash rate decreased from 0.13% in December 2023 to 0.06% in December 2024. Serious injuries (Severity A) decreased from 124 to 88, and minor injuries (Severity B) decreased from 781 to 729. Conversely, possible injury crashes (Severity C) increased from 472 to 523.
Severity is per crash event (most severe injury). 5 fatal crash events resulted in 6 persons killed.
Outcome by Severity (Crash Events)
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · KABCO injury classification scale
Severity Distribution
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Most severe injury per crash record
Top Contributing Factors
The top five contributing factors maintained their rankings, with 'Failing to Yield Right-of-Way' increasing by 62 crashes (5.66%) to 1,157. 'Improper Overtaking/Passing' saw the largest percentage increase among the top factors, rising by 49 crashes (10.08%) to 535. 'Following Too Closely' increased by 5 crashes (0.71%) to 709, while crashes attributed to 'Weather' decreased by 44 from 138 to 94.
Officer-Reported Primary Contributing Cause
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
Crashes occurring in 'CLEAR' weather conditions increased from 5,641 to 6,317, while crashes in 'RAIN' conditions decreased significantly from 1,998 to 985. Similarly, crashes on 'DRY' road surfaces increased from 5,222 to 5,753, whereas those on 'WET' surfaces decreased from 2,603 to 1,500. Crashes during 'DARKNESS, LIGHTED ROAD' decreased from 3,083 to 2,844.
Weather
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Weather condition at time of crash
Lighting
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Lighting condition field
Road Surface
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Road surface condition field
Vehicles & Demographics
The total number of vehicles involved in crashes decreased from 18,546 in December 2023 to 17,862 in December 2024. The top five vehicle makes involved in crashes remained consistent: Toyota, Chevrolet, Ford, Honda, and Nissan. Most top makes saw a decrease in involvement, with Chevrolet decreasing by 170 vehicles and Nissan decreasing by 86 vehicles, while Honda increased by 97 vehicles.
Top Vehicle Makes (17,862 vehicles)
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Vehicle unit records
5,339 persons with unknown or unrecorded age excluded from age chart. Age=0 in Chicago records is a sentinel for unknown/unrecorded age (not infants) and is grouped with nulls.
Sex Distribution (18,954 persons with recorded sex)
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Person-level records linked to crash events
Speed Limit Zones
Crashes in 30 mph speed zones decreased from 6,779 to 6,488, and the fatal crash count in this zone decreased from 8 to 4. The fatal rate for 30 mph zones decreased from 0.118% to 0.062%. In 45 mph zones, crashes decreased from 71 to 57, but the fatal count remained at 1, resulting in an increase in the fatal rate from 1.408% to 1.754%.
Fatal crashes by zone: 30 mph: 4 of 6,488 (0.062%) · 45 mph: 1 of 57 (1.754%)
Source: Chicago Traffic Crashes · Socrata Open Data · 2024-12-01 to 2024-12-31 · Posted speed limit at crash location
Data Sources & Methodology
Primary Data Source
All crash data in this report is sourced from Chicago Traffic Crashes, accessed programmatically via the Socrata Open Data API (SODA). This dataset contains official police-reported motor vehicle traffic crash records maintained by the reporting jurisdiction's law enforcement agency. Records are published to the open data portal by the municipality and are subject to the portal's terms of use.
Data Retrieval
- Access method: Socrata Open Data API (SoQL queries)
- Data format: Structured JSON via REST API
- Record types queried: Crash events, person records, and vehicle unit records
- Date filter applied: 2024-12-01 through 2024-12-31
- Report generated: June 1, 2026
Data Coverage
- Reporting period: 2024-12-01 through 2024-12-31 (31 days)
- Geographic scope: Chicago, IL
- Total crash records analyzed: 8,788
- Total persons involved: 19,343
- Total vehicles involved: 17,862
Analytical Methodology
- Severity classification: Uses the KABCO injury scale (K=Fatal, A=Incapacitating injury, B=Non-incapacitating injury, C=Possible injury, O=No injury/property damage only), the standard classification in U.S. Model Minimum Uniform Crash Criteria (MMUCC). Severity is assigned per crash event based on the most severe injury in that crash. A single fatal crash (K) may involve multiple fatalities; therefore the "Persons Killed" count in the headline KPIs may differ from the "Fatal" crash count in the severity breakdown.
- Contributing factors: Reflect the officer-determined primary contributory cause recorded at the time of the crash report. These are preliminary determinations and may not reflect final investigation findings.
- Hit-and-run classification: Based on the hit-and-run indicator field in the official crash report, as determined by the responding officer at the scene.
- Temporal analysis: Day-of-week and hour-of-day distributions are computed from the crash date/time timestamp in each record.
- Demographics: Age and sex distributions are drawn from person-level records linked to each crash event. A single crash may involve multiple persons.
- Vehicle data: Make information is drawn from vehicle unit records linked to each crash event.
- AI commentary: Narrative sections are generated by Google Gemini (large language model) based on the structured data. Commentary is descriptive, not predictive, and should not be interpreted as expert opinion.
Limitations & Disclaimers
- Only crashes reported to and documented by law enforcement are included. Minor incidents, unreported crashes, and near-misses are not captured in this dataset.
- Data reflects conditions at the time of the initial police report and may be subject to subsequent corrections, reclassifications, or supplements by the reporting agency.
- Open data portal records may experience a publication lag - recently occurring crashes may not yet appear in the dataset at the time of report generation.
- AI-generated commentary is produced by a large language model and is intended to highlight patterns in the data. It does not constitute legal, medical, or professional analysis.
- Percentages are calculated from reported data and are subject to rounding.
Non-Affiliation Disclosure
This report is produced independently by ThatCarHitMe.com (Injuria.ai). It is not affiliated with, endorsed by, or produced in partnership with any law enforcement agency, municipal government, state department of transportation, or the National Highway Traffic Safety Administration (NHTSA). Data is sourced from publicly available government open data portals.
Data License
The underlying crash data is provided under the municipality's Open Data Terms of Use and is made available to the public for unrestricted use. This analysis and report is © 2026 Injuria.ai and may be cited with attribution using the suggested citation below.
Corrections & Feedback
If you believe any data in this report is inaccurate or have questions about our methodology, please contact: data@injuria.ai. We are committed to accuracy and will issue corrections promptly.
Suggested Citation
ThatCarHitMe.com (Injuria.ai). "Chicago, IL Crash Intelligence Report." Published June 1, 2026. Data source: Chicago Traffic Crashes, Socrata Open Data. Available at: https://thatcarhitme.com/crash-data/illinois/chicago/december-2024-report
About the Publisher
ThatCarHitMe.com is a crash data intelligence platform developed by Injuria.ai, a legal technology company specializing in traffic safety analytics. We aggregate and analyze publicly available government crash data to produce structured intelligence reports for communities, researchers, journalists, and legal professionals. Our reports combine programmatic data retrieval from official open data portals with AI-assisted narrative analysis.
Questions about this report's data or methodology: data@injuria.ai
ThatCarHitMe.com · An Injuria.ai Company
ThatCarHitMe.com
An Injuria.ai Company
Crash Data Intelligence
Data: Chicago Traffic Crashes · Socrata
Period: 2024-12-01 – 2024-12-31
Generated: June 1, 2026 · All rights reserved