ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · CHICAGO, IL · JULY 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/july-2021-report
Monthly Traffic Safety Analysis
10,015 CRASHES IN
CHICAGO, IL
JULY 2021
In July 2021, Chicago experienced 10,015 total crashes, an increase of 10.76% compared to the 9,042 crashes recorded in July 2020. Despite the rise in overall crashes, total fatalities decreased significantly by 39.13%, from 23 in the prior period to 14 in the current period. Total injuries also saw an increase of 10.52%, rising from 2,119 to 2,342. This notable decrease in fatalities is the most significant year-over-year shift.
10,015
▲ 10.8%was 9,042
Total Crash Events
14
▼ -39.1%was 23
Persons Killed
2,342
▲ 10.5%was 2,119
Persons Injured
3,439
▲ 8.5%was 3,170
Hit-and-Run Crashes
Note: "Persons Killed" (14) counts individual fatalities across all crash events. "Fatal" in the severity table below (14) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 28 crashes with unreported severity are not shown in the severity breakdown.
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · Aggregate counts from crash, person, and vehicle records
Trend Summary
Overall, crash incidents in Chicago show an upward trend year-over-year, with total crashes increasing by 973, representing a 10.76% rise from July 2020 to July 2021. This increase in crash volume is accompanied by a notable decrease in fatalities, which fell by 39.13%.
3,439
Hit-and-Run Crashes — July 2021
▲ 8.5% vs prior (3,170)
Hit-and-run crashes increased in count by 269, rising from 3,170 in July 2020 to 3,439 in July 2021. However, the overall hit-and-run rate slightly decreased by 0.8 percentage points, from 35.1% to 34.3% of all crashes.
Vulnerable Road User Casualties
3
Pedestrians Killed
2
Cyclists Killed
9
Motorists Killed
0
Other Killed
181
Pedestrians Injured
176
Cyclists Injured
1,982
Motorists Injured
3
Other Injured
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · 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, with 1,761 crashes in July 2021 compared to 1,600 in July 2020. However, the peak hour for crashes shifted from 4 PM in July 2020 (675 crashes) to 3 PM in July 2021 (759 crashes). Saturday saw the largest increase in crash counts, rising by 493 crashes from 1,238 to 1,731.
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · Crash date field aggregated by weekday
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
The fatal crash rate decreased from 0.3% in July 2020 to 0.1% in July 2021, with total fatal crashes falling from 23 to 14. While the proportion of minor injury crashes decreased slightly from 10.2% to 9.8%, serious injury crashes increased from 2.1% to 2.5% of total crashes. No injury crashes maintained a dominant share, rising slightly from 82.7% to 83%.
Outcome by Severity (Crash Events)
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · KABCO injury classification scale
Severity Distribution
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · Most severe injury per crash record
Top Contributing Factors
Failing to Yield Right-of-Way remained the leading contributing factor, increasing by 86 crashes from 935 in July 2020 to 1,021 in July 2021. Following Too Closely also saw a substantial increase of 119 crashes, rising from 782 to 901. Conversely, factors like 'Disregarding Stop Sign' decreased by 28 crashes, and 'Distraction - From Inside Vehicle' decreased by 27 crashes.
Officer-Reported Primary Contributing Cause
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
While clear weather remained the dominant condition for crashes, its share decreased slightly from 89.8% to 87.5% year-over-year. Crashes occurring in rainy conditions increased by 96, and cloudy/overcast conditions saw an increase of 132 crashes. The proportion of crashes on wet road surfaces also rose from 5.5% to 6.6%.
Weather
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · Weather condition at time of crash
Lighting
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · Lighting condition field
Road Surface
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · Road surface condition field
Vehicles & Demographics
The total number of vehicles involved in crashes increased by 1,902, or 10.20%, from 18,643 in July 2020 to 20,545 in July 2021. Chevrolet remained the most involved vehicle make, while Toyota moved from third to second place in terms of crash involvement, with its count increasing by 299 vehicles. All age groups experienced an increase in the number of persons involved in crashes, with the 35-44 age group showing the largest increase of 330 persons.
Top Vehicle Makes (20,545 vehicles)
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · Vehicle unit records
6,638 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 (21,495 persons with recorded sex)
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · Person-level records linked to crash events
Speed Limit Zones
The 30 mph speed zone continued to account for the majority of crashes, increasing by 739 incidents from 6,523 to 7,262. The fatal crash rate in the 25 mph zone saw a significant decrease from 0.657% to 0.146%. However, the 45 mph zone experienced an increase in its fatal crash rate, rising from 0% in July 2020 to 1.099% in July 2021, despite a relatively small increase of 33 crashes in this zone.
Fatal crashes by zone: 25 mph: 1 of 685 (0.146%) · 30 mph: 12 of 7,262 (0.165%) · 45 mph: 1 of 91 (1.099%)
Source: Chicago Traffic Crashes · Socrata Open Data · 2021-07-01 to 2021-07-31 · 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: 2021-07-01 through 2021-07-31
- Report generated: June 1, 2026
Data Coverage
- Reporting period: 2021-07-01 through 2021-07-31 (31 days)
- Geographic scope: Chicago, IL
- Total crash records analyzed: 10,015
- Total persons involved: 21,864
- Total vehicles involved: 20,545
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/july-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: 2021-07-01 – 2021-07-31
Generated: June 1, 2026 · All rights reserved