ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · CHELSEA, MA · JULY 2024
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/massachusetts/chelsea/july-2024-report
Monthly Traffic Safety Analysis
88 CRASHES IN
CHELSEA, MA
JULY 2024
Total crashes in CHELSEA, MA remained stable at 88 in July 2024, matching the 88 crashes reported in July 2023. While total fatalities remained at zero for both periods, hit-and-run crashes saw a notable decrease, falling by 50% from 6 incidents in July 2023 to 3 in July 2024.
88
Total Crash Events
0
Persons Killed
33
▲ 3.1%was 32
Persons Injured
3
▼ -50.0%was 6
Hit-and-Run Crashes
Note: "Persons Killed" (0) counts individual fatalities across all crash events. "Fatal" in the severity table below (0) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 1 crash with unreported severity is not shown in the severity breakdown.
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · Aggregate counts from crash, person, and vehicle records
Trend Summary
The overall number of crashes remained stable year-over-year, with 88 crashes recorded in both July 2024 and July 2023. Total fatalities were consistently zero in both periods. Total injuries saw a slight increase, rising by 3.1% from 32 in July 2023 to 33 in July 2024.
3
Hit-and-Run Crashes — July 2024
▼ -50.0% vs prior (6)
Hit-and-run crashes decreased by 50% year-over-year, falling from 6 incidents in July 2023 to 3 in July 2024. This reduction also led to a decrease in the hit-and-run rate, which dropped from 6.8% in the prior period to 3.4% in the current period.
Vulnerable Road User Casualties
0
Pedestrians Killed
0
Cyclists Killed
0
Motorists Killed
0
Other Killed
1
Pedestrians Injured
1
Cyclists Injured
30
Motorists Injured
1
Other Injured
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · 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 Wednesday in both periods, with 20 crashes in July 2024 and 21 in July 2023. The peak crash hour shifted from 4 PM in July 2023 to 3 PM in July 2024, though both hours recorded 10 crashes. There was a notable increase in crashes on Fridays, rising from 2 in July 2023 to 8 in July 2024.
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · Crash date field aggregated by weekday
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
Fatal crashes remained at zero in both July 2024 and July 2023. Serious injury (A) crashes increased from 1 in July 2023 to 2 in July 2024, with their share of total crashes rising from 1.1% to 2.3%. Minor injury (B) crashes also increased significantly from 7 to 14, while possible injury (C) crashes decreased from 12 to 9.
Outcome by Severity (Crash Events)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · KABCO injury classification scale
Severity Distribution (Crash Events)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · Most severe injury per crash record
Top Contributing Factors
Among contributing factors, 'Other improper action' crashes more than doubled, increasing from 5 in July 2023 to 11 in July 2024. Crashes attributed to 'Failed to yield right of way' also rose from 4 to 7, a 75% increase in count. Conversely, 'No improper driving' crashes decreased from 32 to 27, a 15.6% reduction in count, and 'Operating vehicle in erratic, reckless, careless, negligent or aggressive manner' crashes dropped from 4 to 1.
Officer-Reported Primary Contributing Cause
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
Clear weather remained the dominant condition for crashes, accounting for 77 incidents in July 2024 compared to 76 in July 2023. Crashes occurring in daylight increased from 61 in July 2023 to 68 in July 2024, while those in 'Dark - lighted roadway' conditions decreased from 21 to 14. Dry road surfaces were consistent, with 83 crashes occurring under these conditions in both periods.
Weather
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · Weather condition at time of crash
Lighting
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · Lighting condition field
Road Surface
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · Road surface condition field
Vehicles & Demographics
The age group '35-44' saw an increase in persons involved in crashes, rising from 37 in July 2023 to 46 in July 2024. Similarly, the '55-64' age group experienced a significant increase from 11 to 27 persons. Among vehicle makes, TOYOTA remained the most common, with 41 vehicles involved in July 2024 compared to 42 in July 2023, while JEEP saw a substantial increase from 7 to 18 vehicles.
Top Vehicle Makes (174 vehicles)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · Vehicle unit records
22 persons with unknown or unrecorded age excluded from age chart.
Sex Distribution (201 persons with recorded sex)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · Person-level records linked to crash events
Speed Limit Zones
Crashes in 25 MPH speed zones increased from 65 in July 2023 to 72 in July 2024. Conversely, crashes in 40 MPH speed zones saw a sharp decrease, falling from 9 to 1. Fatalities remained at zero across all reported speed zones in both periods.
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2024-07-01 to 2024-07-31 · Posted speed limit at crash location
Data Sources & Methodology
Primary Data Source
All crash data in this report is sourced from Massachusetts Crash Data (MassDOT CDV), accessed programmatically via the Arcgis_yearly 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: Arcgis_yearly 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: 2024-07-01 through 2024-07-31
- Report generated: June 21, 2026
Data Coverage
- Reporting period: 2024-07-01 through 2024-07-31 (31 days)
- Geographic scope: CHELSEA, MA
- Total crash records analyzed: 88
- Total persons involved: 226
- Total vehicles involved: 174
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). "CHELSEA, MA Crash Intelligence Report: July 2024." Published June 21, 2026. Reporting period: 2024-07-01 to 2024-07-31. Data source: Massachusetts Crash Data (MassDOT CDV), Arcgis_yearly Open Data. Available at: https://thatcarhitme.com/crash-data/massachusetts/chelsea/july-2024-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: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly
Period: 2024-07-01 – 2024-07-31
Generated: June 21, 2026 · All rights reserved