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Document a loss
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Service areas
Middle Tennessee
- Nashville
- Clarksville
- Murfreesboro
- Franklin
- Hendersonville
- Smyrna
- Spring Hill
- Gallatin
- Lebanon
- Columbia
- Brentwood
- Mount Juliet
- La Vergne
- Cookeville
East Tennessee
West Tennessee
Skid-Mark and Tire-Mark Documentation
Identification, measurement and photography of tire marks left before and after a collision, including skids, yaw marks, scuffs and the gouges associated with them. Requested by adjusters, attorneys and reconstruction experts before traffic and weather erase the marks.
- Coverage
- 95 of 95 counties
- Dispatch
- 24 / 7 / 365
- Metro response
- Under 60 min avg.
- Statewide
- 4-hour guarantee
What this service covers
Tire marks are the nearest thing a roadway has to a recording of vehicle movement. A straight, dark skid from a locked wheel, a curved and striated yaw mark from a vehicle sliding sideways while still rolling, and a short collision scuff where a tire was forced across the surface at impact each describe a different event. Telling them apart, and recording each one fully, is the purpose of this assignment.
The marks are also among the most perishable evidence at a scene. Rubber deposits lighten with every passing vehicle and every rainfall, and faint shadow marks at the start of a skid can vanish within a day or two. Vehicles with anti-lock brakes often leave only light, intermittent marks that are easy to miss in overhead sun. Early documentation, in low-angle light where possible, captures detail that will not be there later.
When tire marks carry the dispute
- One driver says the other never braked, and marks on the pavement may show whether and where braking began.
- A vehicle left the roadway on a curve and the yaw marks are the main physical record of its path.
- Several sets of marks from unrelated earlier incidents overlap at the location and need to be distinguished from the collision's marks.
- A commercial vehicle's dual-tire marks must be separated from those of a passenger car in the same lane.
- Rain is forecast or resurfacing is scheduled, and the marks need to be recorded before either removes them.
What is recorded for each tire mark
- Mark type and appearance
- Each mark is classified by its visible characteristics, including darkness, width, edge definition and striation direction, with close photographs that let an analyst confirm the classification.
- Start and end points
- The first faint trace and the termination of each mark are located by measurement from fixed reference points, with the faint lead-in portion flagged for the photographs.
- Length along the path
- Each mark is measured along its actual path. Gaps, skips and overlapping segments from front and rear tires are measured separately.
- Curvature of yaw marks
- Chord and middle ordinate readings are taken at stated points along curved marks, and the striation angle is photographed square-on with a scale.
- Attribution to a wheel
- Track width between paired marks and tread or rib patterns are recorded, so marks can be matched to a specific vehicle and wheel position.
- Surface under the mark
- Pavement type, wear, moisture, contaminants and grade along the mark are noted, along with any change of surface partway through its length.
From request to delivered record
- RequestCall dispatch or submit the request form with the location, loss type and urgency.
- DeployDispatch assigns the nearest available licensed field investigator through the statewide network.
- DocumentPhotographs, video, measurements and factual notes are captured once the scene is safe to work.
- PreserveFiles are timestamped, organized and kept in their original form with a record of who captured them.
- ReportThe package is delivered securely to the requesting party, typically the same day.
What different marks let an analyst examine
A locked-wheel skid records a vehicle sliding under braking, and its measured length on a known surface is one of the standard inputs for examining the speed lost over that distance. A yaw mark records a vehicle rotating while moving forward, and its curvature is used to examine speed through the turn. Collision scuffs and abrupt offsets in a mark indicate where tires were displaced by impact, which helps locate the area of impact on the roadway.
Gouges often sit alongside tire marks and are documented with them. A gouge is cut into the surface by metal, typically when a vehicle's structure is driven downward at maximum engagement, and it outlasts rubber deposits by months. The relationship between where the marks end, where the gouges lie and where the vehicles stopped is what an analyst uses to order the events. The field record supplies those positions. It does not supply a speed figure or a statement of legal fault.
Photographing marks so they can be measured later
A tire mark photographed from standing height in midday sun may barely show. Investigators photograph each mark from both ends looking along its length, from the side, and from directly above at intervals with a scale in the frame. Low sun or an oblique light source brings out faint deposits. Start and end points are flagged with numbered markers before the wide shots are taken, so the photographs and the measurement table identify the same locations without interpretation.
The deliverable includes the mark-by-mark table, photographs, video walking the length of each mark and field notes on conditions at the time. If the retaining party has a reconstruction expert, the data is delivered in a form that expert can use, and any further testing of the surface is a matter for that expert. Delator's personnel have accident reconstruction experience and can report technical findings on request. They do not decide who was at fault.
Delator personnel have accident reconstruction experience. The work product is physical evidence and technical findings; it does not determine legal fault, which remains with the parties, the court or a jury.
Delator Claims Division is not an engineering firm. Whether any analysis is accepted in a proceeding is decided by the court.
Common questions about this service
How long do skid marks stay visible?
It varies with traffic volume, weather and pavement, and no fixed period can be promised. On a busy road, lighter marks can fade noticeably within days, while heavy deposits and gouges last longer. Because the faintest portions disappear first and those portions matter to an analyst, earlier documentation preserves more.
Can you tell which vehicle made a mark?
The investigator records the features that allow attribution: track width, tire width, tread pattern, the mark's alignment with final rest and damage on the tires themselves. Where those features point clearly to one vehicle, the findings say so. Where marks may predate the collision, that uncertainty is stated.
Do you calculate speed from the marks?
A documentation assignment records the marks and the surface and stops there. If you want technical findings, Delator's personnel with accident reconstruction experience can report what the evidence indicates and the assumptions involved. Many clients instead pass the data to their own expert. In no case does the report determine legal fault.
What if the vehicle had anti-lock brakes and left no obvious skid?
Anti-lock systems usually leave lighter, sometimes intermittent marks that can still be found with careful inspection and angled light. The investigator searches the full approach for them and records their absence if none are found. Absence of marks is noted as an observation only, without inference about what the driver did.
Available statewide, including
Every Tennessee county is covered. See the deployment map for typical response tiers by county.
Request documentation anywhere in Tennessee
Dispatch is staffed around the clock. For time-sensitive scenes, calling is fastest; the request form works for routine and scheduled assignments.