ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · MASSACHUSETTS, MA · DECEMBER 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/december-2025-report
Monthly Traffic Safety Analysis
12,042 CRASHES IN
MASSACHUSETTS, MA
DECEMBER 2025
In December 2025, there were 12,042 total crashes, a 7.2% decrease from the 12,977 crashes recorded in December 2024. This downward trend was accompanied by a 16.1% reduction in total injuries, which fell from 3,827 to 3,211. The most notable year-over-year shift was this significant drop in both crashes and resulting injuries, though total fatalities saw a slight increase from 31 to 34.
12,042
▼ -7.2%was 12,977
Total Crash Events
34
▲ 9.7%was 31
Persons Killed
3,211
▼ -16.1%was 3,827
Persons Injured
1,093
▼ -5.0%was 1,150
Hit-and-Run Crashes
Note: "Persons Killed" (34) counts individual fatalities across all crash events. "Fatal" in the severity table below (31) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 415 crashes with unreported severity are not shown in the severity breakdown.
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · Aggregate counts from crash, person, and vehicle records
Trend Summary
The overall trend shows a year-over-year decrease in traffic collisions. Total crashes fell by 7.2%, from 12,977 in December 2024 to 12,042 in December 2025. This reduction was mirrored by a 16.1% drop in injuries, though the number of fatalities increased from 31 to 34 over the same period.
1,093
Hit-and-Run Crashes — December 2025
▼ -5.0% vs prior (1,150)
The absolute number of hit-and-run crashes decreased from 1,150 in December 2024 to 1,093 in December 2025. However, the hit-and-run rate, representing the proportion of all crashes that were hit-and-runs, trended slightly upward from 8.9% to 9.1%. This indicates that hit-and-run incidents constituted a slightly larger percentage of total crashes in the current period compared to the prior year.
Vulnerable Road User Casualties
12
Pedestrians Killed
0
Cyclists Killed
22
Motorists Killed
0
Other Killed
158
Pedestrians Injured
28
Cyclists Injured
3,005
Motorists Injured
20
Other Injured
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · Mode classified from person records (driver/passenger → motorist; pedestrian; bicyclist → cyclist; in-line skater / unspecified → other)
When Crashes Happen
The peak hour for crashes remained 5 p.m. in both periods, though the crash count during this hour fell from 1,215 to 1,096. A significant shift occurred in the peak day of the week, moving from Friday (2,254 crashes) in December 2024 to Tuesday (2,183 crashes) in December 2025. This change indicates a redistribution of crash occurrences throughout the week compared to the previous year.
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · Crash date field aggregated by weekday
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
The fatal crash rate increased from 0.22% in December 2024 to 0.26% in December 2025, with the count of fatal crashes rising from 29 to 31. The share of crashes resulting in any form of injury (Serious, Minor, or Possible) declined, accounting for a combined 20.1% of incidents compared to 21.7% in the prior year. Consequently, the proportion of crashes involving no injuries rose from 73.9% to 76.2% year-over-year.
Severity is per crash event (most severe injury). 31 fatal crash events resulted in 34 persons killed.
Outcome by Severity (Crash Events)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · KABCO injury classification scale
Severity Distribution (Crash Events)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · Most severe injury per crash record
Top Contributing Factors
The top five contributing factors remained unchanged in ranking between December 2024 and December 2025, led by "No improper driving," "Inattention," and "Failed to yield right of way." The count of crashes attributed to "Inattention" decreased by 9.5% from 1,492 to 1,350, while crashes related to "Followed too closely" fell by 7.4% from 1,107 to 1,025. In contrast, the number of crashes where "Driving too fast for conditions" was a factor increased by 18.7%, from 475 to 564 incidents.
Officer-Reported Primary Contributing Cause
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
The distribution of crashes by lighting conditions was stable, with daylight crashes accounting for approximately 51% of the total in both periods. There was a shift in road surface conditions, as the share of crashes on dry roads increased from 61.5% in December 2024 to 64.2% in December 2025. Correspondingly, the proportion of crashes occurring on adverse surfaces such as wet, snow, or ice decreased from 36.4% to 33.8% year-over-year.
Weather
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · Weather condition at time of crash
Lighting
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · Lighting condition field
Road Surface
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · Road surface condition field
Vehicles & Demographics
The top three vehicle makes involved in collisions were Toyota, Honda, and Ford in both periods, with the count for each make decreasing in line with the overall reduction in crashes. The age distribution of all persons involved in crashes remained highly consistent year-over-year. For instance, the 26-34 age group represented 16.6% of persons in the prior period and a nearly identical 16.7% in the current period, with no significant demographic shifts observed.
Top Vehicle Makes (21,929 vehicles)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · Vehicle unit records
2,790 persons with unknown or unrecorded age excluded from age chart.
Sex Distribution (23,765 persons with recorded sex)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · Person-level records linked to crash events
Speed Limit Zones
The distribution of crashes shifted slightly toward higher speed zones, with incidents in zones of 55 mph or more increasing their share from 10.0% in December 2024 to 11.7% in December 2025. Fatalities in these high-speed zones decreased from 5 to 3. Conversely, the number of fatalities in mid-range speed zones (35-50 mph) increased from 8 to 14, while fatalities in lower speed zones (30 mph or less) rose from 11 to 13.
Fatal crashes by zone: 25 mph: 4 of 2,728 (0.147%) · 30 mph: 9 of 3,089 (0.291%) · 35 mph: 5 of 1,530 (0.327%) · 40 mph: 7 of 952 (0.735%) · 45 mph: 1 of 405 (0.247%) · 50 mph: 1 of 270 (0.37%) · 55 mph: 1 of 514 (0.195%) · 65 mph: 2 of 744 (0.269%)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-12-01 to 2025-12-31 · 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: 2025-12-01 through 2025-12-31
- Report generated: June 21, 2026
Data Coverage
- Reporting period: 2025-12-01 through 2025-12-31 (31 days)
- Geographic scope: massachusetts, MA
- Total crash records analyzed: 12,042
- Total persons involved: 26,722
- Total vehicles involved: 21,929
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: December 2025." Published June 21, 2026. Reporting period: 2025-12-01 to 2025-12-31. Data source: Massachusetts Crash Data (MassDOT CDV), Arcgis_yearly Open Data. Available at: https://thatcarhitme.com/crash-data/massachusetts/statewide/december-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: 2025-12-01 – 2025-12-31
Generated: June 21, 2026 · All rights reserved