ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · DEDHAM, MA · 2022
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/dedham/2022-annual-report
Yearly Traffic Safety Analysis
436 CRASHES IN
DEDHAM, MA
2022
In 2022, Dedham recorded 436 total vehicle crashes, an 8.5% increase from the 402 crashes reported in 2021. While the total number of crashes and fatalities rose from 4 to 5, the number of people injured in these incidents decreased by 18%. The most significant year-over-year shift by percentage was a 47% increase in the count of hit-and-run crashes, which rose from 17 to 25.
436
▲ 8.5%was 402
Total Crash Events
5
▲ 25.0%was 4
Persons Killed
155
▼ -18.0%was 189
Persons Injured
25
▲ 47.1%was 17
Hit-and-Run Crashes
Note: "Persons Killed" (5) counts individual fatalities across all crash events. "Fatal" in the severity table below (5) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 32 crashes with unreported severity are not shown in the severity breakdown.
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · Aggregate counts from crash, person, and vehicle records
Trend Summary
Year-over-year, total crashes in Dedham increased by 8.5%, rising from 402 in 2021 to 436 in 2022. Despite this rise in crash volume, the number of people injured decreased by 18%, from 189 to 155. The number of fatalities increased from 4 to 5 during the same period.
25
Hit-and-Run Crashes — 2022
▲ 47.1% vs prior (17)
The number of hit-and-run incidents increased significantly year-over-year. In 2022, there were 25 hit-and-run crashes, a 47% increase from the 17 incidents recorded in 2021. The hit-and-run rate, which measures the proportion of total crashes that are hit-and-runs, also trended upward, rising from 4.2% in 2021 to 5.7% in 2022.
Vulnerable Road User Casualties
2
Pedestrians Killed
0
Cyclists Killed
3
Motorists Killed
0
Other Killed
2
Pedestrians Injured
2
Cyclists Injured
150
Motorists Injured
1
Other Injured
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · Mode classified from person records (driver/passenger → motorist; pedestrian; bicyclist → cyclist; in-line skater / unspecified → other)
When Crashes Happen
The temporal patterns of crashes showed some shifts between the two periods. While the most common time for a crash remained the 5 PM hour in both years, the number of incidents during this peak hour increased from 33 to 42. The peak day for crashes shifted from Thursday in 2021 (66 crashes) to a tie between Tuesday and Friday in 2022, each with 71 crashes.
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · Crash date field aggregated by weekday
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
The severity of crashes shifted year-over-year, with a decrease in reported injuries despite an increase in total crashes. The number of fatal crashes increased from 4 to 5, and the fatal crash rate rose from 1.0% to 1.15%. Conversely, crashes resulting in serious injuries dropped from 8 incidents in 2021 to 3 in 2022. The proportion of crashes involving any type of injury decreased from 30.8% of all crashes in 2021 to 25.9% in 2022.
Outcome by Severity (Crash Events)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · KABCO injury classification scale
Severity Distribution (Crash Events)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · Most severe injury per crash record
Top Contributing Factors
The leading contributing factors cited in crashes remained largely consistent, though their counts generally increased. 'Followed too closely' was the top factor in both years, rising from 50 to 53 incidents. A notable increase was observed in crashes related to 'Failed to yield right of way,' which grew in count by 78% from 18 incidents in 2021 to 32 in 2022. Crashes involving 'Failure to keep in proper lane or running off road' also increased from 24 to 33.
Officer-Reported Primary Contributing Cause
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
Crash conditions remained broadly similar year-over-year. In both 2021 and 2022, approximately 80% of crashes occurred on dry roads, and about two-thirds of incidents happened during daylight hours. Crashes in clear weather accounted for the majority of incidents in both periods, with 70.9% in 2021 and 69.0% in 2022. There was no significant shift in the proportion of crashes occurring under adverse weather, road, or lighting conditions.
Weather
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · Weather condition at time of crash
Lighting
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · Lighting condition field
Road Surface
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · Road surface condition field
Vehicles & Demographics
The demographic profile of persons involved in crashes shifted slightly, with the 35-44 age group becoming the most represented cohort in 2022 (199 people), up from 147 the prior year. The number of individuals aged 65 and older involved in crashes also increased from 88 to 132. Regarding vehicles, the top three most common makes involved in collisions remained consistent: Toyota (156 vehicles in 2022 vs. 119 in 2021), Honda (116 vs. 110), and Ford (88 vs. 83).
Top Vehicle Makes (827 vehicles)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · Vehicle unit records
62 persons with unknown or unrecorded age excluded from age chart.
Sex Distribution (944 persons with recorded sex)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · Person-level records linked to crash events
Speed Limit Zones
The distribution of crashes across different speed limit zones was largely unchanged between the two years. The 55 mph zone accounted for the highest number of crashes in both 2021 (128 crashes) and 2022 (121 crashes). In 2022, fatal crashes were recorded in zones with speed limits of 35, 40, 45, and 55 mph. This contrasts with 2021, where fatalities occurred in 35, 45, and 55 mph zones, but not in the 40 mph zone.
Fatal crashes by zone: 35 mph: 2 of 46 (4.348%) · 40 mph: 1 of 4 (25%) · 45 mph: 1 of 53 (1.887%) · 55 mph: 1 of 121 (0.826%)
Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2022-01-01 to 2022-12-31 · 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: 2022-01-01 through 2022-12-31
- Report generated: June 21, 2026
Data Coverage
- Reporting period: 2022-01-01 through 2022-12-31 (365 days)
- Geographic scope: DEDHAM, MA
- Total crash records analyzed: 436
- Total persons involved: 1,012
- Total vehicles involved: 827
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). "DEDHAM, MA Crash Intelligence Report: 2022." Published June 21, 2026. Reporting period: 2022-01-01 to 2022-12-31. Data source: Massachusetts Crash Data (MassDOT CDV), Arcgis_yearly Open Data. Available at: https://thatcarhitme.com/crash-data/massachusetts/dedham/2022-annual-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: 2022-01-01 – 2022-12-31
Generated: June 21, 2026 · All rights reserved