ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · CHICAGO, IL · MAY 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/may-2017-report
Monthly Traffic Safety Analysis
5,847 CRASHES IN
CHICAGO, IL
MAY 2017
Total crashes in May 2017 were 5,847, a substantial increase of 89.16% compared to 3,091 crashes in May 2016. Concurrently, total fatalities rose from 3 in May 2016 to 6 in May 2017, marking a 100% increase. The most notable year-over-year shift is the significant increase in overall crash volume.
5,847
▲ 89.2%was 3,091
Total Crash Events
6
▲ 100.0%was 3
Persons Killed
674
▲ 158.2%was 261
Persons Injured
1,563
▲ 91.8%was 815
Hit-and-Run Crashes
Note: "Persons Killed" (6) counts individual fatalities across all crash events. "Fatal" in the severity table below (3) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 8 crashes with unreported severity are not shown in the severity breakdown.
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · Aggregate counts from crash, person, and vehicle records
Trend Summary
The overall trend indicates a substantial increase in crash incidents year-over-year. Total crashes rose by 89.16%, from 3,091 in May 2016 to 5,847 in May 2017. Total injuries also increased significantly, from 261 to 674, representing a 158.24% rise.
1,563
Hit-and-Run Crashes — May 2017
▲ 91.8% vs prior (815)
Hit-and-run crashes increased by 91.78% from 815 in May 2016 to 1,563 in May 2017. The hit-and-run rate remained relatively stable, increasing slightly from 26.4% of all crashes in May 2016 to 26.7% in May 2017.
Vulnerable Road User Casualties
1
Pedestrians Killed
0
Cyclists Killed
5
Motorists Killed
72
Pedestrians Injured
28
Cyclists Injured
574
Motorists Injured
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · 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 Tuesday in May 2016 (535 crashes) to Wednesday in May 2017 (968 crashes). The peak hour also shifted from 3 PM in May 2016 (264 crashes) to 4 PM in May 2017 (525 crashes). This suggests a general increase in crash activity across all days and hours, with a slight shift in the precise timing of peak incidents.
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · Crash date field aggregated by weekday
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
While the number of fatal crashes remained constant at 3 in both periods, the total number of fatalities increased from 3 in May 2016 to 6 in May 2017, a 100% rise. The fatal crash rate decreased from 0.1% to 0.05% due to the overall increase in total crashes. Injury crashes of all severities saw significant increases: serious injury crashes rose from 20 to 58 (190% increase), minor injury crashes from 80 to 241 (201.25% increase), and possible injury crashes from 83 to 180 (116.87% increase).
Severity is per crash event (most severe injury). 3 fatal crash events resulted in 6 persons killed.
Outcome by Severity (Crash Events)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · KABCO injury classification scale
Severity Distribution
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · Most severe injury per crash record
Top Contributing Factors
The top contributing factor, 'FOLLOWING TOO CLOSELY', increased in count from 414 to 747, an 80.4% rise, while its share decreased from 13.4% to 12.8%. 'FAILING TO YIELD RIGHT-OF-WAY' saw a 136.5% increase in count, from 282 to 667, and its share rose from 9.1% to 11.4%. Notably, 'DRIVING SKILLS/KNOWLEDGE/EXPERIENCE' decreased in count by 29.38%, from 194 to 137, and its share dropped from 6.3% to 2.3%, falling out of the top three factors.
Officer-Reported Primary Contributing Cause
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
Crashes occurring in 'CLEAR' weather conditions increased from 2,453 in May 2016 to 4,730 in May 2017, while 'RAIN' condition crashes increased from 307 to 684. For road surface, 'DRY' condition crashes rose from 2,444 to 4,584, and 'WET' condition crashes increased from 387 to 867. In terms of lighting, crashes during 'DAYLIGHT' increased from 2,283 to 4,441, and 'DARKNESS, LIGHTED ROAD' crashes increased from 441 to 777.
Weather
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · Weather condition at time of crash
Lighting
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · Lighting condition field
Road Surface
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · Road surface condition field
Vehicles & Demographics
The total number of vehicles involved in crashes increased by 89.5%, from 6,201 in May 2016 to 11,751 in May 2017. Similarly, the total number of persons involved rose by 90.9%, from 6,851 to 13,080. All age groups saw increases in persons involved, with the 0-15 age group showing the largest percentage increase at 113.9%, from 222 to 475. The top vehicle makes involved, Chevrolet, Toyota, and Ford, maintained their rankings and saw increases in counts proportional to the overall crash increase.
Top Vehicle Makes (11,751 vehicles)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · Vehicle unit records
4,174 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 (12,954 persons with recorded sex)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · Person-level records linked to crash events
Speed Limit Zones
Crashes occurring in 30 mph speed zones increased from 2,181 in May 2016 to 4,377 in May 2017, a 100.7% rise, with fatal crashes in this zone increasing from 1 to 3. In 20 mph zones, crashes increased from 109 to 190, but fatal crashes decreased from 1 to 0. Similarly, 35 mph zones saw crashes increase from 229 to 339, but fatal crashes decreased from 1 to 0.
Fatal crashes by zone: 30 mph: 3 of 4,377 (0.069%)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-05-01 to 2017-05-31 · 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: 2017-05-01 through 2017-05-31
- Report generated: June 1, 2026
Data Coverage
- Reporting period: 2017-05-01 through 2017-05-31 (31 days)
- Geographic scope: Chicago, IL
- Total crash records analyzed: 5,847
- Total persons involved: 13,080
- Total vehicles involved: 11,751
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/may-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: 2017-05-01 – 2017-05-31
Generated: June 1, 2026 · All rights reserved