Monthly Traffic Safety Analysis

524 CRASHES IN
BOSTON, MA
DECEMBER 2023

All metrics benchmarked againstDecember 2022

In December 2023, Boston recorded 524 crashes, a slight decrease of 1.87% compared to the 534 crashes in December 2022. However, total fatalities increased significantly by 300%, rising from 1 fatality in the prior period to 4 fatalities in the current period. This notable increase in fatalities represents the most significant year-over-year shift in crash outcomes.

524

-1.9%was 534

Total Crash Events

4

300.0%was 1

Persons Killed

188

19.7%was 157

Persons Injured

65

-4.4%was 68

Hit-and-Run Crashes

Note: "Persons Killed" (4) counts individual fatalities across all crash events. "Fatal" in the severity table below (4) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 24 crashes with unreported severity are not shown in the severity breakdown.

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · Aggregate counts from crash, person, and vehicle records

Trend Summary

Overall crash incidents in Boston showed a slight downward trend, with a 1.87% decrease from 534 crashes in December 2022 to 524 crashes in December 2023. Despite fewer total crashes, there was a concerning upward trend in fatalities, which quadrupled from 1 to 4 during the same period. Total injuries also rose by 19.75%, from 157 to 188.

65

Hit-and-Run Crashes — December 2023

-4.4% vs prior (68)

Hit-and-run incidents experienced a slight decrease year-over-year, falling from 68 crashes in December 2022 to 65 crashes in December 2023. The hit-and-run rate also showed a minor decline, moving from 12.7% in the prior period to 12.4% in the current period, indicating a downward trend.

Vulnerable Road User Casualties

1

Pedestrians Killed

Prior: 10.0%

1

Cyclists Killed

Prior: 0%

2

Motorists Killed

Prior: 0%

0

Other Killed

Prior: 00.0%

12

Pedestrians Injured

Prior: 22-45.5%

3

Cyclists Injured

Prior: 6-50.0%

171

Motorists Injured

Prior: 12932.6%

2

Other Injured

Prior: 0%

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · Mode classified from person records (driver/passenger → motorist; pedestrian; bicyclist → cyclist; in-line skater / unspecified → other)

When Crashes Happen

The temporal patterns for crashes shifted year-over-year. The peak day for crashes moved from Saturday with 104 incidents in December 2022 to Friday with 98 incidents in December 2023. Similarly, the peak hour for crashes shifted from 7p with 39 incidents in the prior period to 5p with 37 incidents in the current period.

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · Crash date field aggregated by weekday

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · Crash time field aggregated by hour (0-23)

Crash Severity Breakdown

The severity distribution of crashes saw notable changes, with fatal crashes increasing from 1 (0.2% of total crashes) in December 2022 to 4 (0.8% of total crashes) in December 2023. Serious injury crashes also rose from 6 (1.1% share) to 9 (1.7% share) year-over-year. Conversely, minor injury crashes decreased slightly from 78 to 77, while possible injury crashes increased from 45 to 49.

Outcome by Severity (Crash Events)

Fatal4fatal crashes0.8%
300.0%prior 1
Serious Injury9serious injury crashes1.7%
50.0%prior 6
Minor Injury77minor injury crashes14.7%
-1.3%prior 78
Possible Injury49possible injury crashes9.4%
8.9%prior 45
No Injury361no injury crashes68.9%
3.1%prior 350

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · KABCO injury classification scale

Severity Distribution (Crash Events)

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · Most severe injury per crash record

Top Contributing Factors

Among contributing factors, 'No improper driving' crashes decreased by 19 incidents, from 115 in December 2022 to 96 in December 2023. Crashes attributed to 'Failed to yield right of way' increased by 12 incidents, rising from 39 to 51, marking a 30.8% increase in count. 'Disregarded traffic signs, signals, road markings' also saw a notable increase of 8 crashes, from 21 to 29, a 38.1% increase in count.

Officer-Reported Primary Contributing Cause

No improper driving96 (18.3%)-16.5%prior 115
Followed too closely63 (12%)3.3%prior 61
Failed to yield right of way51 (9.7%)30.8%prior 39
Disregarded traffic signs, signals, road markings29 (5.5%)38.1%prior 21
Inattention20 (3.8%)-13.0%prior 23
Other improper action20 (3.8%)100.0%prior 10
Failure to keep in proper lane or running off road20 (3.8%)-39.4%prior 33
Exceeded authorized speed limit19 (3.6%)-9.5%prior 21
Driving too fast for conditions18 (3.4%)-21.7%prior 23
Made an improper turn15 (2.9%)-11.8%prior 17

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · Officer-reported primary contributory cause per crash

Road & Environmental Conditions

Regarding environmental conditions, crashes occurring in 'Clear' weather increased by 19, from 307 to 326 incidents. Crashes in 'Rain' decreased by 8, from 97 to 89, and 'Cloudy' conditions saw a decrease of 12 crashes, from 47 to 35. On road surfaces, crashes on 'Wet' roads decreased by 8, from 126 to 118, while those on 'Snow' decreased by 11, from 12 to 1. Lighting conditions saw a decrease of 24 crashes each for 'Dark - lighted roadway' and 'Daylight' conditions.

Weather

Clear326 (67.9%)
6.2%prior 307
Rain89 (18.5%)
-8.2%prior 97
Cloudy35 (7.3%)
-25.5%prior 47
Cloudy/Rain16 (3.3%)
128.6%prior 7
Fog, smog, smoke5 (1.0%)
Rain/Cloudy3 (0.6%)
Other2 (0.4%)
Snow2 (0.4%)
-86.7%prior 15
Rain/Other1 (0.2%)
Clear/Cloudy1 (0.2%)

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · Weather condition at time of crash

Lighting

Dark - lighted roadway251 (51.6%)
-8.7%prior 275
Daylight188 (38.7%)
-11.3%prior 212
Dawn14 (2.9%)
27.3%prior 11
Dusk11 (2.3%)
57.1%prior 7
Dark - roadway not lighted9 (1.9%)
50.0%prior 6
Other7 (1.4%)
Dark - unknown roadway lighting6 (1.2%)

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · Lighting condition field

Road Surface

Dry333 (73.3%)
-0.3%prior 334
Wet118 (26.0%)
-6.3%prior 126
Ice2 (0.4%)
-66.7%prior 6
Snow1 (0.2%)
-91.7%prior 12

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · Road surface condition field

Vehicles & Demographics

The total number of vehicles involved in crashes decreased slightly from 1046 in December 2022 to 1026 in December 2023. The top three vehicle makes involved in crashes remained consistent: Toyota, Honda, and Ford. While Toyota saw an increase of 8 vehicles involved (from 194 to 202), Honda and Ford experienced decreases of 11 and 9 vehicles respectively.

Top Vehicle Makes (1,026 vehicles)

1
TOYOTA202 (19.7%)
4.1%prior 194
2
HONDA147 (14.3%)
-7.0%prior 158
3
FORD103 (10%)
-8.0%prior 112
4
NISSAN69 (6.7%)
23.2%prior 56
5
CHEVROLET53 (5.2%)
-15.9%prior 63
6
JEEP39 (3.8%)
-20.4%prior 49
7
HYUNDAI30 (2.9%)
-11.8%prior 34
8
SUBARU28 (2.7%)
3.7%prior 27
9
MAZDA24 (2.3%)
26.3%prior 19
10
MERCEDES-BENZ22 (2.1%)
-15.4%prior 26

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · Vehicle unit records

161 persons with unknown or unrecorded age excluded from age chart.

Sex Distribution (1,060 persons with recorded sex)

Male656 (61.9%)
-2.8%prior 675
Female404 (38.1%)
-1.0%prior 408

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · Person-level records linked to crash events

Speed Limit Zones

Crashes occurring in 25 mph speed zones saw a notable shift in fatality rates, increasing from 0 fatal crashes out of 191 total crashes in December 2022 to 4 fatal crashes out of 188 total crashes in December 2023. Conversely, the 55 mph speed zone experienced a decrease in fatal crashes, going from 1 fatality out of 61 crashes in the prior period to 0 fatalities out of 53 crashes in the current period.

Fatal crashes by zone: 25 mph: 4 of 188 (2.128%)

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2023-12-01 to 2023-12-31 · 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: 2023-12-01 through 2023-12-31
  • Report generated: June 21, 2026

Data Coverage

  • Reporting period: 2023-12-01 through 2023-12-31 (31 days)
  • Geographic scope: BOSTON, MA
  • Total crash records analyzed: 524
  • Total persons involved: 1,253
  • Total vehicles involved: 1,026

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). "BOSTON, MA Crash Intelligence Report: December 2023." Published June 21, 2026. Reporting period: 2023-12-01 to 2023-12-31. Data source: Massachusetts Crash Data (MassDOT CDV), Arcgis_yearly Open Data. Available at: https://thatcarhitme.com/crash-data/massachusetts/boston/december-2023-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

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Boston, MA Crash Report — December 2023 | ThatCarHitMe.com