ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · CHICAGO, IL · APRIL 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/april-2017-report
Monthly Traffic Safety Analysis
5,024 CRASHES IN
CHICAGO, IL
APRIL 2017
Total crashes in April 2017 increased to 5024, a 73.1% rise from 2902 crashes recorded in April 2016. A significant year-over-year shift was observed in fatalities, which increased from 0 in the prior period to 2 in the current period. This indicates a substantial increase in overall crash incidents and the emergence of fatal outcomes.
5,024
▲ 73.1%was 2,902
Total Crash Events
2
Persons Killed
509
▲ 112.1%was 240
Persons Injured
1,394
▲ 86.9%was 746
Hit-and-Run Crashes
Note: "Persons Killed" (2) counts individual fatalities across all crash events. "Fatal" in the severity table below (2) 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 · 2017-04-01 to 2017-04-30 · Aggregate counts from crash, person, and vehicle records
Trend Summary
The overall trend indicates a substantial increase in crash activity year-over-year. Total crashes rose by 73.1%, from 2902 in April 2016 to 5024 in April 2017. Additionally, the number of fatalities increased from 0 to 2 during the same period.
1,394
Hit-and-Run Crashes — April 2017
▲ 86.9% vs prior (746)
Hit-and-run crashes increased by 86.9% in count, rising from 746 in April 2016 to 1394 in April 2017. The hit-and-run rate also trended upwards, increasing from 25.7% of all crashes in April 2016 to 27.7% in April 2017.
Vulnerable Road User Casualties
0
Pedestrians Killed
0
Cyclists Killed
2
Motorists Killed
0
Other Killed
52
Pedestrians Injured
28
Cyclists Injured
428
Motorists Injured
1
Other Injured
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · 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 April 2016, with 556 incidents, to Saturday in April 2017, with 938 incidents. The peak hour for crashes remained consistent at 3 PM in both periods, though the count at this hour increased from 268 in April 2016 to 406 in April 2017.
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · Crash date field aggregated by weekday
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
The fatal crash rate increased from 0% in April 2016 to 0.04% in April 2017, corresponding to an increase from 0 to 2 fatal crashes. The proportion of serious injury (A) crashes slightly increased from 0.8% to 0.9%, while minor injury (B) crashes saw a larger increase from 2.5% to 3.7% of total crashes. Conversely, the proportion of no injury (O) crashes decreased from 94% to 92.3%.
Outcome by Severity (Crash Events)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · KABCO injury classification scale
Severity Distribution
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · Most severe injury per crash record
Top Contributing Factors
Several contributing factors saw notable increases in count year-over-year. Crashes attributed to 'FOLLOWING TOO CLOSELY' increased by 77.2%, from 355 to 629 incidents. 'FAILING TO YIELD RIGHT-OF-WAY' incidents rose by 58.8%, from 325 to 516, and 'IMPROPER OVERTAKING/PASSING' incidents increased by 66.1%, from 165 to 274. Notably, 'EXCEEDING AUTHORIZED SPEED LIMIT' saw a substantial 246.7% increase in count, rising from 15 to 52 incidents.
Officer-Reported Primary Contributing Cause
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
Crashes occurring in clear weather conditions increased by 1786 incidents, from 2109 to 3895, though their share of total crashes rose only slightly from 72.7% to 77.5%. Incidents during rainy weather increased by 435, from 381 to 816, with their share of total crashes rising from 13.1% to 16.2%. Crashes involving snow decreased significantly, from 94 incidents in April 2016 to only 2 in April 2017.
Weather
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · Weather condition at time of crash
Lighting
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · Lighting condition field
Road Surface
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · Road surface condition field
Vehicles & Demographics
The total number of vehicles involved in crashes increased by 73.7%, from 5833 to 10131. The count of pedestrians involved in crashes saw a 200% increase, rising from 23 to 69, while bicycle involvement increased by 155%, from 20 to 51. The top vehicle makes involved, Chevrolet, Toyota, and Ford, maintained their leading positions, all experiencing similar percentage increases in their counts.
Top Vehicle Makes (10,131 vehicles)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · Vehicle unit records
3,572 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 (10,974 persons with recorded sex)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · Person-level records linked to crash events
Speed Limit Zones
Crashes in the 30 mph speed zone increased by 75.4%, from 2114 in April 2016 to 3708 in April 2017, and this zone accounted for all 2 fatal crashes in the current period. The 30 mph zone remained the predominant speed limit for crashes in both periods. There were no fatalities recorded in any speed zone in April 2016.
Fatal crashes by zone: 30 mph: 2 of 3,708 (0.054%)
Source: Chicago Traffic Crashes · Socrata Open Data · 2017-04-01 to 2017-04-30 · 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: 2017-04-01 through 2017-04-30
- Report generated: June 1, 2026
Data Coverage
- Reporting period: 2017-04-01 through 2017-04-30 (30 days)
- Geographic scope: Chicago, IL
- Total crash records analyzed: 5,024
- Total persons involved: 11,112
- Total vehicles involved: 10,131
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/april-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: 2017-04-01 – 2017-04-30
Generated: June 1, 2026 · All rights reserved