ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · CHICAGO, IL · AUGUST 2017
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/august-2017-report
Monthly Traffic Safety Analysis
7,685 CRASHES IN
CHICAGO, IL
AUGUST 2017
Total crashes in Chicago increased by 72.27% year-over-year, rising from 4461 in August 2016 to 7685 in August 2017. The most notable shift was a significant increase in total fatalities, which rose by 450% from 2 to 11 during the same period. This indicates a substantial increase in both crash volume and severity.
7,685
▲ 72.3%was 4,461
Total Crash Events
11
▲ 450.0%was 2
Persons Killed
1,434
▲ 290.7%was 367
Persons Injured
1,953
▲ 66.9%was 1,170
Hit-and-Run Crashes
Note: "Persons Killed" (11) counts individual fatalities across all crash events. "Fatal" in the severity table below (11) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 12 crashes with unreported severity are not shown in the severity breakdown.
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · Aggregate counts from crash, person, and vehicle records
Trend Summary
The overall trend shows a significant increase in crash activity year-over-year. Total crashes rose from 4461 in August 2016 to 7685 in August 2017, representing a 72.27% increase. Concurrently, the number of fatalities more than quintupled, from 2 to 11.
1,953
Hit-and-Run Crashes — August 2017
▲ 66.9% vs prior (1,170)
The count of hit-and-run crashes increased from 1170 in August 2016 to 1953 in August 2017, representing a 66.92% rise. Despite this increase in raw numbers, the hit-and-run rate slightly decreased from 26.2% of total crashes in August 2016 to 25.4% in August 2017.
Vulnerable Road User Casualties
2
Pedestrians Killed
0
Cyclists Killed
9
Motorists Killed
165
Pedestrians Injured
145
Cyclists Injured
1,124
Motorists Injured
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · Mode classified from person records (driver/passenger → motorist; pedestrian; bicyclist → cyclist; in-line skater / unspecified → other)
When Crashes Happen
The peak day for crashes shifted from Friday in August 2016 (707 crashes) to Wednesday in August 2017 (1286 crashes). Similarly, the peak hour moved from 3 PM (379 crashes) in August 2016 to 5 PM (588 crashes) in August 2017. All days of the week and hours of the day experienced an increase in crash counts year-over-year.
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · Crash date field aggregated by weekday
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
The total number of fatalities increased significantly from 2 in August 2016 to 11 in August 2017, causing the fatal crash rate to rise from 0.04% to 0.14%. Total injuries also saw a substantial increase from 367 to 1434 year-over-year. The share of serious injury crashes (severity A) rose from 0.8% to 1.8% of total crashes, while the share of 'No Injury' crashes decreased from 93.7% to 86%.
Outcome by Severity (Crash Events)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · KABCO injury classification scale
Severity Distribution
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · Most severe injury per crash record
Top Contributing Factors
"FAILING TO YIELD RIGHT-OF-WAY" increased in count from 415 to 928, a 123.6% change, becoming the top contributing factor in August 2017. "FOLLOWING TOO CLOSELY" increased from 566 to 920 crashes, a 62.5% change, moving from the top spot to second. "IMPROPER BACKING" also saw an increase in count from 280 to 358 crashes, a 27.9% change, maintaining its position as the third most frequent factor.
Officer-Reported Primary Contributing Cause
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
Crashes occurring in "CLEAR" weather conditions increased in count from 3783 to 6827, an 80.47% rise. Crashes during "DAYLIGHT" hours rose from 3245 to 5502, a 69.57% increase, while those in "DARKNESS, LIGHTED ROAD" conditions more than doubled, from 612 to 1306, a 113.4% increase. This indicates a general increase in crash volume across various conditions, with some adverse lighting conditions seeing particularly high percentage increases in crash counts.
Weather
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · Weather condition at time of crash
Lighting
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · Lighting condition field
Road Surface
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · Road surface condition field
Vehicles & Demographics
The total number of vehicles involved in crashes increased from 8964 to 15676, a 74.88% rise. The top vehicle make involved shifted, with Chevrolet becoming the most frequent (1848 incidents) in August 2017, surpassing Toyota (1738 incidents) which was previously the top make (1100 incidents). All reported age groups showed an increase in the number of persons involved in crashes year-over-year.
Top Vehicle Makes (15,676 vehicles)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · Vehicle unit records
4,890 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 (16,830 persons with recorded sex)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · Person-level records linked to crash events
Speed Limit Zones
Crashes in 30 mph zones increased from 3328 in August 2016 to 5552 in August 2017, with fatal crashes in this zone rising from 1 to 6. In 25 mph zones, crashes increased from 291 to 487, and fatal crashes in this zone rose from 0 to 2. The highest number of fatal crashes for both periods occurred in the 30 mph speed limit zone.
Fatal crashes by zone: 15 mph: 2 of 280 (0.714%) · 25 mph: 2 of 487 (0.411%) · 30 mph: 6 of 5,552 (0.108%) · 35 mph: 1 of 619 (0.162%)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-08-01 to 2017-08-31 · 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: 2017-08-01 through 2017-08-31
- Report generated: June 1, 2026
Data Coverage
- Reporting period: 2017-08-01 through 2017-08-31 (31 days)
- Geographic scope: Chicago, IL
- Total crash records analyzed: 7,685
- Total persons involved: 17,027
- Total vehicles involved: 15,676
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/august-2017-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: 2017-08-01 – 2017-08-31
Generated: June 1, 2026 · All rights reserved