Truck accident cases are won or lost on evidence—and most of it can disappear faster than people realize. Memories fade. Vehicles get repaired or sold. Skid marks wash away. Electronic data can be overwritten.
Meanwhile, the trucking company’s defense team often starts building their case within hours, and much of the critical evidence is already in their control.
If you were hit by a commercial truck, knowing what evidence exists—and how to preserve it—can make the difference between a fair recovery and a denied claim.
At Keith & Lorfing, we represent truck accident victims across West Texas and act quickly to secure the proof that matters most. If you’re unsure what evidence may still be available in your case, speaking with an Abilene Truck Accident Lawyer can help you take the right steps before it’s too late.
This guide breaks down the key evidence used in trucking cases, why it matters, and how it’s preserved.
Why Evidence Preservation Is Different in a Truck Case
In an ordinary car accident, the main evidence is the police report, photos, and witness statements. In a commercial truck case, that is just the surface. Federal regulations require carriers to keep extensive records, and modern trucks generate large amounts of electronic data.
The challenge is timing. Much of that evidence has a short retention window. Some categories may be overwritten in days. Others can be discarded within months of the crash unless someone formally demands preservation.
A spoliation letter, sent by your attorney within days of the crash, requires the carrier and its insurer to maintain all relevant evidence. Without that letter, the records may legally disappear.
Physical Evidence at the Scene
The crash scene contains evidence that can never be fully reproduced later.
- Photographs and video. Vehicle positions, damage patterns, debris field, road conditions, weather, and surrounding signage.
- Skid marks and yaw marks. Show speed, braking, and steering inputs.
- Gouge marks and scrape patterns. Indicate point of first contact and direction of travel.
- Debris field. The location and pattern of broken parts can confirm impact angle and speed.
- Vehicle damage. Crush patterns, paint transfer, and component damage tell a reconstruction story.
- Cargo and load condition. Shifted, fallen, or unsecured cargo can prove improper loading.
- Roadway conditions. Lane markings, signage, sight obstructions, and pavement defects.
When possible, our investigators reach the scene within hours to document conditions before they change.
The Truck’s Electronic Data (“Black Box” Information)
Modern commercial trucks carry several layers of electronic data, often referred to collectively as “black box” data. Most of it is time-sensitive.
Engine Control Module (ECM)
The ECM, sometimes called the truck’s electronic data recorder, captures vehicle performance data in the seconds and minutes before a hard event. Depending on the manufacturer and configuration, it can record:
- Vehicle speed
- Engine RPM
- Throttle position
- Brake application and pressure
- Cruise control status
- Seatbelt status
- Hard braking and acceleration events
- Diagnostic trouble codes
ECM data is overwritten as new events occur. A second hard event after the crash can overwrite the original data. Pulling the data with a manufacturer-approved tool, with proper chain of custody, must happen quickly.
Electronic Logging Device (ELD)
Required by federal law for most commercial drivers, the ELD records duty status, drive time, on-duty time, off-duty time, sleeper berth time, engine on/off events, motion, and location—key data used to uncover truck driver hours of service violations. ELDs link the driver’s logged activity to the truck’s actual movement.
Carriers must retain ELD records for at least 6 months. Drivers must keep copies for 8 days, then transfer them to the carrier. Edits to ELD records are tracked, and edit history often shows attempted concealment.
Telematics and GPS Data
Many carriers run third-party telematics systems separate from the ELD. These can record location, speed, hard braking events, lane departure, following distance, and driver scoring. Retention varies by provider, often 90 to 365 days unless preservation is requested.
Dashcam and Forward-Facing Cameras
Forward-facing and driver-facing cameras have become widespread. They typically record continuously on a loop, saving longer clips when triggered by a hard event. Loop video is overwritten in days unless preserved. Even when a hard event clip is saved, carriers sometimes “lose” it without a preservation letter.
Collision Mitigation and ADAS Data
Newer trucks may carry advanced driver assistance systems that record radar, camera, and lane-departure data. Each manufacturer stores this data differently, and pulling it usually requires manufacturer-specific tools.
Driver Records
The driver’s own records are often as important as the truck’s data.
- Driver Qualification File (DQF). Required by 49 CFR 391. Includes employment history, road test, motor vehicle record, medical certificate, and annual inquiries.
- Drug and alcohol testing records. Pre-employment, post-accident, random, and reasonable-suspicion test results.
- Driver’s CDL and endorsements. Confirms qualification for the type of vehicle and cargo.
- Driver’s medical certification. Confirms fitness to drive under DOT physical standards.
- Training records. Initial training, remedial training, and any specialty training.
- Personnel file. Disciplinary records, prior incidents, and warnings.
- Cellphone records. Show calls, texts, and app usage at the time of the crash.
Federal rules give the carrier responsibility for keeping these records. Inconsistencies between the DQF and other documents can be devastating to the defense.
Driver Logs and Supporting Documents
Even with ELDs in place, supporting documents are essential for cross-checking.
- Bills of lading and trip envelopes
- Shipping manifests
- Fuel and toll receipts
- Truck stop receipts (food, lodging)
- Weigh station and inspection records
- Driver vehicle inspection reports (DVIRs)
- Dispatch logs and load assignments
- Detention and waiting time records
When the ELD shows the driver off-duty but a fuel receipt shows the truck was actively fueling, or a dispatch log shows the driver loading freight, the off-duty entry is suspect.
Maintenance and Inspection Records
Federal rules require carriers to systematically inspect, repair, and maintain every vehicle in their control. The records this generates are central to mechanical-failure cases such as brake or tire failures.
- Annual periodic inspections (49 CFR 396.17)
- Driver Vehicle Inspection Reports (DVIRs)
- Repair invoices and work orders
- Parts records
- Tire records (purchase, mounting, rotation, retread)
- Maintenance program documents
Gaps, inconsistencies, or missing records can be powerful proof of negligence.
The Carrier’s Records
The carrier itself produces a wide range of business records that matter in litigation.
- Safety policies and procedures. Often inconsistent with actual day-to-day operations.
- Dispatch and load-planning records. Show the schedule the driver was asked to keep.
- Pay structures and bonus plans. Mileage-based pay and bonus plans can incentivize HOS violations.
- Internal accident reports. Carrier’s own investigation file, often more candid than the public version.
- Risk management correspondence. Communications with the insurer about the loss.
- CSA (Compliance, Safety, Accountability) scores. FMCSA’s public scoring of the carrier’s safety performance.
- Prior FMCSA inspection and violation history. Pattern evidence of past safety failures.
- Insurance policies. Including primary, excess, and umbrella coverage.
Many of these records are obtained only through formal discovery in a lawsuit. That is why pre-suit settlements often shortchange injured people. The most damaging records never come to light.
Witness Evidence
Human witnesses still matter, even in a data-rich case.
- Independent eyewitnesses. Often the most credible source.
- Other commercial drivers. Frequent observers of unsafe trucks and willing to talk.
- First responders. Police officers, paramedics, and firefighters.
- The investigating trooper. Usually the author of the official crash report.
- Treating physicians. Critical for tying injuries to the crash.
- Co-workers, family, and friends. For “before and after” damages testimony.
- Expert witnesses. Reconstruction, mechanical, human factors, vocational, and economic experts.
Witnesses move and forget. Locking down statements early matters.
Government and Public Records
Several public records help build the case.
- Texas Peace Officer’s Crash Report (CR-3). Filed by the responding agency.
- 911 audio. Captures the immediate report of the crash.
- Roadway design and inspection records. From TxDOT or the relevant authority.
- Federal Motor Carrier Safety Administration (FMCSA) records. Carrier’s safety profile, inspection history, and registered insurance.
- Court records of prior crashes and lawsuits involving the carrier or driver.
These records are usually obtainable directly without going through the defendants.
Medical Evidence
Damages depend on medical evidence. Insurers and juries pay attention to documentation.
- Emergency room and hospital records
- Imaging studies (X-ray, CT, MRI)
- Operative reports and discharge summaries
- Physical therapy and rehabilitation notes
- Pain management records
- Mental health treatment records (especially for PTSD claims)
- Pharmacy and prescription records
- Future care projections from treating physicians
- Life-care plans for catastrophic injuries
- Independent medical evaluations when appropriate
Gaps in treatment, missed appointments, or non-compliance with treatment plans are routinely used by defense lawyers.
Damages Evidence
To prove what the case is worth, additional evidence is required.
- Medical bills and explanations of benefits (EOBs)
- Lien notices from health insurers and Medicare/Medicaid
- Wage records (W-2s, 1099s, pay stubs, tax returns)
- Employer letters confirming missed work
- Vocational expert reports
- Economic expert reports calculating future earning loss
- Personal journals documenting day-to-day pain and limitations
- Photographs and video of injuries during recovery
- Statements from family describing the impact on daily life
This category is where the difference between a “case” and a fully valued case is made.
How Evidence Gets Preserved
Preserving evidence is a process. Done correctly, it includes:
- Spoliation letter. Sent to the carrier, the driver, the insurer, and any third parties such as repair shops or shippers. Identifies the categories of evidence that must not be destroyed.
- Vehicle preservation. The truck and trailer are held for inspection before any repair, sale, or release.
- Data download. ECM, ELD, telematics, and dashcam data are pulled with proper chain of custody.
- Records request. Formal demands for driver qualification files, maintenance records, dispatch logs, and policies.
- Litigation hold. When suit is filed, formal duty to preserve attaches under Texas civil rules and federal regulations.
Failure to preserve, when properly documented, can result in spoliation sanctions, including jury instructions that assume the missing evidence was unfavorable to the defendant.
The clock starts the moment your crash happens. If you were hit by a commercial truck, call our West Texas truck accident attorneys at (325) 480-8100 or contact our Abilene Truck Accident lawyer for a free consultation. We send preservation letters fast so the evidence is still there when we need it.
Frequently Asked Questions
How fast does black box data disappear?
ECM data can be overwritten by subsequent events within days. Dashcam loop video can be overwritten within days. Other data has longer retention but still requires preservation.
Can the trucking company refuse to turn over their records?
They can try. Once a lawsuit is filed, formal discovery rules and court orders compel production. Refusal can result in sanctions.
What if the truck was already repaired or sold before I got an attorney?
That is potentially spoliation. Texas courts have remedies, including adverse-inference jury instructions and, in serious cases, dismissal of defenses.
Do I need an attorney to preserve evidence?
Effectively, yes. Preservation letters carry weight when issued by a lawyer who can follow up with a lawsuit. Self-help letters are routinely ignored.
What if I waited weeks before contacting an attorney?
Hire one now. Some evidence is gone, but much of it is still recoverable. Government records, medical records, and many carrier records remain accessible months after the crash.
