ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · CHICAGO, IL · NOVEMBER 2021
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/november-2021-report
Monthly Traffic Safety Analysis
8,774 CRASHES IN
CHICAGO, IL
NOVEMBER 2021
Total crashes in Chicago increased from 6,964 in November 2020 to 8,774 in November 2021, representing a 26.00% rise. The most significant year-over-year change was a 233.33% increase in total fatalities, from 6 in November 2020 to 20 in November 2021.
8,774
▲ 26.0%was 6,964
Total Crash Events
20
▲ 233.3%was 6
Persons Killed
1,733
▲ 17.2%was 1,479
Persons Injured
2,913
▲ 21.8%was 2,391
Hit-and-Run Crashes
Note: "Persons Killed" (20) counts individual fatalities across all crash events. "Fatal" in the severity table below (18) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 24 crashes with unreported severity are not shown in the severity breakdown.
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · Aggregate counts from crash, person, and vehicle records
Trend Summary
Overall, crash activity in Chicago showed a notable upward trend year-over-year. Total crashes increased by 26.00%, from 6,964 in November 2020 to 8,774 in November 2021. This period also saw a substantial 233.33% increase in total fatalities, rising from 6 to 20, and a 17.17% increase in total injuries, from 1,479 to 1,733.
2,913
Hit-and-Run Crashes — November 2021
▲ 21.8% vs prior (2,391)
Hit-and-run crashes increased by 21.83% in count, from 2,391 in November 2020 to 2,913 in November 2021. However, the hit-and-run crash rate decreased slightly from 34.3% to 33.2% of all crashes.
Vulnerable Road User Casualties
7
Pedestrians Killed
1
Cyclists Killed
12
Motorists Killed
201
Pedestrians Injured
61
Cyclists Injured
1,471
Motorists Injured
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · Mode classified from person records (driver/passenger → motorist; pedestrian; bicyclist → cyclist; in-line skater / unspecified → other)
When Crashes Happen
In November 2021, the peak day for crashes shifted to Tuesday with 1,478 incidents, compared to Monday with 1,052 incidents in November 2020. The peak crash hour remained 3 PM for both periods, increasing from 542 crashes in November 2020 to 698 crashes in November 2021.
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · Crash date field aggregated by weekday
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
The number of fatal crashes increased significantly from 6 in November 2020 to 18 in November 2021, a 200% rise. Consequently, the fatal crash rate increased from 0.09% to 0.21% year-over-year. While the share of serious injury crashes decreased slightly from 2.0% to 1.7%, the total number of serious injuries increased from 139 to 145.
Severity is per crash event (most severe injury). 18 fatal crash events resulted in 20 persons killed.
Outcome by Severity (Crash Events)
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · KABCO injury classification scale
Severity Distribution
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · Most severe injury per crash record
Top Contributing Factors
Failing to Yield Right-of-Way remained the top contributing factor, increasing by 43.29% in count from 686 to 983 incidents. Improper Overtaking/Passing saw a 54.74% increase in count, rising from 285 to 441 incidents, making it the third most frequent factor in November 2021. Driving Skills/Knowledge/Experience also experienced a substantial 48.28% increase in count, from 203 to 301.
Officer-Reported Primary Contributing Cause
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
Crashes occurring in CLEAR weather conditions increased by 26.78% in count, from 5,710 to 7,239, while crashes in RAIN decreased by 32.39% in count, from 759 to 513. Similarly, crashes on DRY road surfaces increased by 27.02% in count, from 5,562 to 7,065, whereas crashes on WET surfaces decreased by 9.47% in count, from 929 to 841. Crashes during DAYLIGHT increased by 26.12% in count, from 3,748 to 4,727, and crashes in DARKNESS, LIGHTED ROAD increased by 29.02% in count, from 2,088 to 2,694.
Weather
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · Weather condition at time of crash
Lighting
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · Lighting condition field
Road Surface
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · Road surface condition field
Vehicles & Demographics
The total number of vehicles involved in crashes increased by 25.47%, from 14,301 to 17,943. The count of DRIVER type vehicles involved increased by 27.88% (from 11,731 to 15,001), and PEDESTRIAN type vehicles increased by 39.88% (from 168 to 235). Among top makes, HONDA saw a significant 44.65% increase in count, from 981 to 1,419. The number of persons aged 26-34 involved in crashes increased by 26.31% (from 2,428 to 3,067), and female persons involved increased by 33.87% (from 5,347 to 7,158).
Top Vehicle Makes (17,943 vehicles)
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · Vehicle unit records
6,150 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 (18,840 persons with recorded sex)
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · Person-level records linked to crash events
Speed Limit Zones
Crashes in 30 MPH speed zones increased by 28.23% in count, from 5,055 to 6,482, and the number of fatal crashes in these zones doubled from 6 to 12. Fatal crashes in 25 MPH zones increased from 0 to 2, and in 35 MPH zones increased from 0 to 3. The fatal crash rate in 30 MPH zones increased from 0.119% to 0.185%.
Fatal crashes by zone: 25 mph: 2 of 575 (0.348%) · 30 mph: 12 of 6,482 (0.185%) · 35 mph: 3 of 546 (0.549%) · 40 mph: 1 of 95 (1.053%)
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-11-01 to 2021-11-30 · 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: 2021-11-01 through 2021-11-30
- Report generated: June 1, 2026
Data Coverage
- Reporting period: 2021-11-01 through 2021-11-30 (30 days)
- Geographic scope: Chicago, IL
- Total crash records analyzed: 8,774
- Total persons involved: 19,140
- Total vehicles involved: 17,943
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/november-2021-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: 2021-11-01 – 2021-11-30
Generated: June 1, 2026 · All rights reserved