ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · MASSACHUSETTS, MA · MAY 2025
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/statewide/may-2025-report
Monthly Traffic Safety Analysis
11,401 CRASHES IN
MASSACHUSETTS, MA
MAY 2025
In May 2025, there were 11,401 total crashes, representing a 3.0% decrease from the 11,758 crashes recorded in May 2024. While overall crashes and total injuries (3,607 vs. 3,708) declined, the number of fatalities rose from 29 to 32. A notable year-over-year shift was the increase in pedestrian fatalities, which rose from one in the prior period to five in the current period.
11,401
▼ -3.0%was 11,758
Total Crash Events
32
▲ 10.3%was 29
Persons Killed
3,607
▼ -2.7%was 3,708
Persons Injured
1,089
▼ -0.5%was 1,095
Hit-and-Run Crashes
Note: "Persons Killed" (32) counts individual fatalities across all crash events. "Fatal" in the severity table below (29) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 485 crashes with unreported severity are not shown in the severity breakdown.
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Aggregate counts from crash, person, and vehicle records
Trend Summary
Overall crash trends show a slight year-over-year decline, with total crashes falling by 3.0% from 11,758 in May 2024 to 11,401 in May 2025. Total reported injuries also decreased by 2.7% from 3,708 to 3,607. In contrast to these trends, total fatalities increased by 10.3%, rising from 29 to 32 over the same period.
1,089
Hit-and-Run Crashes — May 2025
▼ -0.5% vs prior (1,095)
The total number of hit-and-run crashes was nearly unchanged, with 1,089 incidents in May 2025 compared to 1,095 in May 2024. However, due to the overall decrease in total crashes, the hit-and-run rate as a percentage of all crashes trended upward. The rate increased from 9.3% in the prior period to 9.6% in the current period.
Vulnerable Road User Casualties
5
Pedestrians Killed
3
Cyclists Killed
24
Motorists Killed
0
Other Killed
116
Pedestrians Injured
133
Cyclists Injured
3,333
Motorists Injured
25
Other Injured
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Mode classified from person records (driver/passenger → motorist; pedestrian; bicyclist → cyclist; in-line skater / unspecified → other)
When Crashes Happen
The timing of crashes remained largely consistent year-over-year. Friday was the peak day for crashes in both May 2025 (2,077 crashes) and May 2024 (2,168 crashes). The peak hour for collisions shifted slightly from the 3 p.m. hour in the prior period (1,028 crashes) to the 4 p.m. hour in the current period (1,035 crashes), keeping the peak firmly in the afternoon commute window.
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Crash date field aggregated by weekday
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
The severity of crashes showed mixed changes compared to the prior year. The number of fatal crashes increased from 27 to 29, and their share of all crashes rose from 0.2% to 0.3%. Conversely, crashes resulting in serious injuries decreased in both count (from 212 to 186) and proportion (from 1.8% to 1.6%). The share of crashes resulting in no injury increased slightly from 71.7% to 72.3%.
Severity is per crash event (most severe injury). 29 fatal crash events resulted in 32 persons killed.
Outcome by Severity (Crash Events)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · KABCO injury classification scale
Severity Distribution (Crash Events)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Most severe injury per crash record
Top Contributing Factors
The top three contributing factors remained the same across both periods: 'No improper driving,' 'Inattention,' and 'Failed to yield right of way.' The count of crashes attributed to 'Inattention' decreased by 7.4% from 1,694 to 1,569, while its share of all crashes fell from 14.4% to 13.8%. Crashes related to 'Followed too closely' saw a 12.1% decrease in count, from 1,152 to 1,012 incidents.
Officer-Reported Primary Contributing Cause
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
There was a significant shift in crashes occurring under adverse road conditions. In May 2025, 22.1% of all crashes (2,523) occurred on wet roads, a notable increase from the 14.6% (1,713 crashes) reported in May 2024. Lighting conditions remained stable, with daylight crashes accounting for approximately 78% of all incidents in both periods.
Weather
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Weather condition at time of crash
Lighting
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Lighting condition field
Road Surface
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Road surface condition field
Vehicles & Demographics
Vehicle and person demographics involved in crashes showed high stability year-over-year. The top three vehicle makes involved in collisions were Toyota, Honda, and Ford in both May 2025 and May 2024, with their rankings unchanged. The age distribution of all persons involved also remained consistent, with no significant proportional shifts observed among age groups like '16-20' or '65+' between the two periods.
Top Vehicle Makes (21,386 vehicles)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Vehicle unit records
2,903 persons with unknown or unrecorded age excluded from age chart.
Sex Distribution (23,628 persons with recorded sex)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Person-level records linked to crash events
Speed Limit Zones
The distribution of crashes across speed zones shifted slightly toward lower-speed areas. In May 2025, 62.5% of crashes with a recorded speed limit occurred in zones of 30 mph or less, up from 60.5% in May 2024. The fatality rate in the 30 mph zone increased from 0.185% to 0.220%, while the rate in the 65 mph zone decreased from 0.758% to 0.528%.
Fatal crashes by zone: 25 mph: 3 of 2,885 (0.104%) · 30 mph: 6 of 2,728 (0.22%) · 35 mph: 4 of 1,337 (0.299%) · 40 mph: 6 of 783 (0.766%) · 45 mph: 2 of 378 (0.529%) · 50 mph: 1 of 289 (0.346%) · 55 mph: 1 of 430 (0.233%) · 65 mph: 4 of 757 (0.528%)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · 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: 2025-05-01 through 2025-05-31
- Report generated: June 21, 2026
Data Coverage
- Reporting period: 2025-05-01 through 2025-05-31 (31 days)
- Geographic scope: massachusetts, MA
- Total crash records analyzed: 11,401
- Total persons involved: 26,701
- Total vehicles involved: 21,386
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). "massachusetts, MA Crash Intelligence Report: May 2025." Published June 21, 2026. Reporting period: 2025-05-01 to 2025-05-31. Data source: Massachusetts Crash Data (MassDOT CDV), Arcgis_yearly Open Data. Available at: https://thatcarhitme.com/crash-data/massachusetts/statewide/may-2025-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: 2025-05-01 – 2025-05-31
Generated: June 21, 2026 · All rights reserved