ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · CHICAGO, IL · MARCH 2018
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/march-2018-report
Monthly Traffic Safety Analysis
9,319 CRASHES IN
CHICAGO, IL
MARCH 2018
In March 2018, Chicago experienced a significant increase in traffic incidents compared to March 2017, with total crashes rising from 5105 to 9319, an 82.54% increase. Fatalities also saw a substantial rise, from 5 to 12, marking a 140% increase year-over-year. The most notable shift was in total injuries, which surged from 367 to 1640, representing a 346.87% increase.
9,319
▲ 82.5%was 5,105
Total Crash Events
12
▲ 140.0%was 5
Persons Killed
1,640
▲ 346.9%was 367
Persons Injured
2,502
▲ 75.7%was 1,424
Hit-and-Run Crashes
Note: "Persons Killed" (12) counts individual fatalities across all crash events. "Fatal" in the severity table below (10) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 19 crashes with unreported severity are not shown in the severity breakdown.
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · Aggregate counts from crash, person, and vehicle records
Trend Summary
Overall, crash data for March 2018 indicates a substantial upward trend in traffic incidents compared to March 2017. Total crashes increased by 4214, rising from 5105 to 9319, which is an 82.54% increase. This suggests a significant increase in crash frequency year-over-year.
2,502
Hit-and-Run Crashes — March 2018
▲ 75.7% vs prior (1,424)
Hit-and-run crashes increased by 75.7% year-over-year, rising from 1424 in March 2017 to 2502 in March 2018. Despite this increase in count, the overall hit-and-run rate slightly decreased from 27.9% of total crashes in March 2017 to 26.8% in March 2018.
Vulnerable Road User Casualties
3
Pedestrians Killed
0
Cyclists Killed
9
Motorists Killed
223
Pedestrians Injured
51
Cyclists Injured
1,366
Motorists Injured
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · Mode classified from person records (driver/passenger → motorist; pedestrian; bicyclist → cyclist; in-line skater / unspecified → other)
When Crashes Happen
Temporal patterns remained consistent in terms of peak day and hour, with Friday remaining the day with the most crashes and 4 PM the peak hour for both periods. Crashes on Fridays increased by 73.56% from 991 in March 2017 to 1720 in March 2018. The number of crashes during the 4 PM peak hour rose by 86.15%, from 426 to 793.
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · Crash date field aggregated by weekday
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
The fatal crash rate increased from 0.06% in March 2017 to 0.11% in March 2018. While the share of fatal crashes remained at 0.1% of total crashes, the number of serious injury crashes increased by 406.67%, from 30 to 152. Minor injury crashes also saw a substantial rise of 440.83%, increasing from 120 to 649.
Severity is per crash event (most severe injury). 10 fatal crash events resulted in 12 persons killed.
Outcome by Severity (Crash Events)
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · KABCO injury classification scale
Severity Distribution
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · Most severe injury per crash record
Top Contributing Factors
The top contributing factor, 'FAILING TO YIELD RIGHT-OF-WAY', increased by 104.52%, rising from 553 crashes in March 2017 to 1131 in March 2018, also moving from the second to the first ranked factor. 'FOLLOWING TOO CLOSELY' crashes increased by 67.92%, from 583 to 979, shifting from the first to the second ranked factor. 'IMPROPER BACKING' saw a 108.25% increase, rising from 206 to 429 crashes.
Officer-Reported Primary Contributing Cause
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
There was a notable shift in crash conditions, with crashes occurring in 'CLEAR' weather increasing by 117.85% (from 3764 to 8200) and on 'DRY' road surfaces increasing by 124.49% (from 3552 to 7974). Conversely, crashes in 'RAIN' decreased by 26.61% (from 575 to 422) and on 'SNOW OR SLUSH' decreased by 83.74% (from 326 to 53). Crashes occurring in 'DARKNESS, LIGHTED ROAD' conditions increased by 124.12%, from 883 to 1979.
Weather
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · Weather condition at time of crash
Lighting
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · Lighting condition field
Road Surface
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · Road surface condition field
Vehicles & Demographics
The total number of vehicles involved in crashes increased by 84.83%, from 10230 in March 2017 to 18908 in March 2018. Notably, pedestrian-involved vehicles increased by 372.73% (from 55 to 260), and bicycle-involved vehicles increased by 315.79% (from 19 to 79). Chevrolet became the top vehicle make involved in crashes in March 2018 with 2196 vehicles, an 82.39% increase from 1204, surpassing Toyota which was the top make in March 2017.
Top Vehicle Makes (18,908 vehicles)
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · Vehicle unit records
5,990 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 (20,644 persons with recorded sex)
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · Person-level records linked to crash events
Speed Limit Zones
Crashes in the 30 mph speed zone, which remained the most frequent zone for crashes, increased by 76.6% from 3867 to 6829. The fatal crash count in this zone increased from 1 to 8, with the fatal rate rising from 0.026% to 0.117%. Crashes in the 35 mph zone saw a 125.35% increase, rising from 284 to 640, and fatal crashes in this zone increased from 0 to 2.
Fatal crashes by zone: 30 mph: 8 of 6,829 (0.117%) · 35 mph: 2 of 640 (0.313%)
Source: Chicago Traffic Crashes · Socrata Open Data · 2018-03-01 to 2018-03-31 · 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: 2018-03-01 through 2018-03-31
- Report generated: June 1, 2026
Data Coverage
- Reporting period: 2018-03-01 through 2018-03-31 (31 days)
- Geographic scope: Chicago, IL
- Total crash records analyzed: 9,319
- Total persons involved: 20,953
- Total vehicles involved: 18,908
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/march-2018-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: 2018-03-01 – 2018-03-31
Generated: June 1, 2026 · All rights reserved