Event data recorders: what your car records and who can access it

Most recent cars sold in the United States carry an event data recorder, a small unit that keeps a short record of what the vehicle was doing just before and during a serious impact: speed, braking, accelerator position, whether the driver's belt was buckled, and whether airbags fired. Federal law says the data belongs to the vehicle's owner or lessee, and others may retrieve it only with the owner's consent, a court order, or one of a few narrow exceptions. The data can settle a fault argument or undercut a driver's story, which is why preserving it matters.

An event data recorder (EDR) is not a dashcam and does not follow you around. It records nothing during ordinary driving. This article explains what it stores, who can read it, how it differs from the connected-car and insurance-app data that follow you all the time, and what to do in the weeks after a crash.

What an event data recorder is

An EDR is usually a function of the vehicle's airbag control module, not a separate black box. The module watches for a sudden change in speed. When that change crosses a threshold, it saves a snapshot of the data it has been holding in a short rolling buffer.

Federal rules define the threshold. Under 49 CFR Part 563, an "event" occurs when a longitudinal change in speed equals or exceeds 8 km/h (about 5 mph) within a 150-millisecond interval, or when a non-reversible airbag or restraint deploys, whichever happens first (49 CFR 563.5). So a parking-lot bump may not trigger a record, while a moderate collision usually does.

The rule is a standard for the data that an EDR must record if the vehicle has one. It does not require manufacturers to install one. Part 563 applies to passenger cars, multipurpose passenger vehicles, trucks and buses with a gross vehicle weight rating of 8,500 pounds or less and an unloaded weight of 5,500 pounds or less (49 CFR 563.3). Heavier commercial trucks fall outside Part 563, though many have engine control modules that keep their own records of hard braking and speed. See crashes with commercial trucks and delivery vehicles: what changes for how that changes a claim.

What it stores

The regulation lists data elements that every covered EDR must record and others that are recorded only if the vehicle has the feature. The list in 49 CFR 563.7, as published in the federal regulations in November 2026, includes:

For the pre-crash items, the regulation's table now calls for a window running from 20 seconds before the event, with a phase-in for vehicles produced starting in 2028, while earlier-model vehicles are held to a shorter window of about five seconds recorded a few times per second. That means the data on a car built before the phase-in is a short, coarse picture: a handful of speed readings in the last few seconds before impact. A vehicle manufacturer's owner's manual must describe what its recorder does.

The same federal rule requires the owner's manual to say that the recorder's main purpose is to capture data during certain crashes or near-crashes, that the data cover a short period (typically 30 seconds or less), and that the recorder does not capture data during normal driving. The manual statement also says the EDR does not record the driver's name, gender, age or the crash location, and that reading it takes special equipment (49 CFR 563.11).

What it does not store

• It does not record audio or video, and it does not store a continuous log of your trips.
• It does not normally record your name or personal details, though law enforcement can match the data to a vehicle's VIN and to the crash investigation.
• It does not record a phone call or text. Whether a phone was in use is established in other ways, such as phone records.
• Many EDRs do not record location. Some connected-car systems do, but that is a different system, described below.

What happens to the record afterward

The rules on storage matter if you want to preserve a record. In an airbag-deployment crash, the module must lock that event so a later crash cannot overwrite it. For non-deployment events, the recorder keeps up to two events, and the manufacturer may overwrite an earlier non-deployment event with a newer one if it has no free memory (49 CFR 563.9). In practice, a minor impact that did not set off the airbags can be erased by a later impact. Whether and how a given car overwrites depends on its design.

Who owns the data

Before 2015 the answer varied by state, and the federal government said it lacked authority to decide. The Driver Privacy Act of 2015, enacted as part of the FAST Act in December 2015, settled the principle for the whole country. It says data stored on an EDR belongs to the vehicle's owner or, in the case of a leased vehicle, the lessee. That rule applies to a vehicle regardless of when it was manufactured.

The Act also limits who else can read the data. Under its text (see the note to 49 U.S.C. 30101), someone other than the owner or lessee can retrieve it only in these cases:

1. A court or administrative order. A judicial or administrative authority with jurisdiction authorizes retrieval, and the data must meet that body's standards for admission of evidence.
2. Consent. The owner or lessee agrees, in writing, electronically or by recorded audio, to retrieval for any purpose, including diagnosis, service or repair. Consent can also come through a subscription service agreement that explains how data will be retrieved and used.
3. A federal safety investigation. The retrieval is part of an investigation or inspection under federal safety statutes, and personal information and the VIN are withheld (the VIN may go to the manufacturer).
4. Emergency medical response. The data is retrieved to determine or support the medical response to a crash.
5. Traffic safety research. The data is used for research without disclosing personal information or the VIN.

The Act does not say that an insurance company can demand the data. An insurer's route is consent, which can come from the owner, or a court order.

State laws

States have their own EDR statutes, and the details differ. Two examples show the pattern.

California's Vehicle Code section 9951 applies to vehicles made on or after July 1, 2004. Recorded data may not be downloaded by anyone other than the registered owner unless the owner consents, a court orders it, it is retrieved for safety or medical research with the owner's identity withheld, or a licensed dealer or automotive technician needs it to diagnose or repair the vehicle. Manufacturers must disclose the device in the owner's manual.

Texas's Transportation Code section 547.615 likewise limits retrieval by anyone other than the owner to cases of a court order, owner consent, vehicle-safety or medical research that does not identify the owner or driver, and determining or facilitating emergency medical response after a collision. It defines the "owner" to include a titleholder, a buyer in possession under a security agreement, and a lessee under a lease of at least three months, and it requires manufacturers to disclose recording devices in owner's manuals. The section contains no insurance-specific provisions.

Several other states have similar laws, and a few add specific rules about insurers, so check your own state's statute or ask the state insurance department.

Who actually reads it, and how

Data is not read from a dashboard. A technician connects a commercial crash-data retrieval tool to the vehicle's diagnostic port or directly to the module and generates a report. Tool support is not universal across brands and model years, and a few vehicles require the module to be removed and read on the bench. The report is generated as a file that can be preserved and shared.

The most common readers are:

• Insurers. An insurer investigating a disputed claim may ask the policyholder to consent to a download. This is part of your duty to cooperate under the policy, discussed in the cooperation clause: records, interviews and exams under oath. Whether refusing consent could affect coverage depends on the policy language and state law, so ask the insurer what it is asking for and why, and consider legal advice before refusing.
• Police and prosecutors. In a serious or fatal crash, police may get a warrant or court order. Because the data belongs to the owner, consent or a warrant is the usual route.
• Attorneys and experts. In a lawsuit, either side's reconstruction expert may ask to image the data, and a court can order it.
• Repair shops and dealers. Technicians access the module for repair, which is why many EDR statutes carve out a repair exception.
• Manufacturers. A manufacturer may request data for safety investigations, subject to the Driver Privacy Act.

For how this data is used in disputed claims and fraud investigations, see event data recorders as evidence in claims and fraud cases.

EDR data versus the data your car and phone send all the time

An EDR is a crash snapshot. Several other systems collect data continuously and are governed by different rules:

The difference matters. The EDR has a federal ownership rule. Connected-car and telematics data is governed mainly by contracts and by consumer-protection and privacy law, an area that is changing. For instance, the Federal Trade Commission approved a final order with General Motors and its OnStar service on January 14, 2026, that, as reported, bars the company from sharing certain location and driving-behavior data with consumer reporting agencies for five years and requires affirmative consent for collecting connected-vehicle data (FTC announcement). Read the terms of any connected service before agreeing, and see connected-car data, data brokers and your premium and what driving apps collect and how insurers use it.

If you enrolled in an insurer's usage-based program, that data is a separate record from the EDR and may be used for rating or in a dispute; can your telematics data be used in a claim or a lawsuit? covers that, and plug-in device, phone app or built-in car data: which tracking method? compares the sources.

How EDR data helps or hurts in a fault dispute

Used well, the record can end an argument. Say two drivers disagree about a collision at an intersection. One claims the other was speeding. A recorder report might show that the car was moving at 28 mph, the brake switch changed to "on" about 1.5 seconds before the impact, and the accelerator was at 0% for the last second. That would support a driver who says they saw the other car late and braked, and it would undercut a claim that they were flooring it. The numbers here are made up for illustration.

Used badly, the same record can hurt. If the same report shows 48 mph in a 35 mph zone, no braking until the impact, and a driver's belt unbuckled, the driver's account will be hard to defend, and the unbuckled belt could reduce an injury claim in states that allow a seat belt defense (the seat belt defense: when not buckling up cuts your claim).

Its limits

An EDR is a piece of evidence, not an oracle.

• Speed is derived. In many vehicles, recorded speed comes from the wheel-speed sensors. Heavy braking, wheel lock, non-standard tire sizes or a skid can make it differ from true ground speed, so experts treat it as an estimate with a margin of error.
• Change in speed is not impact speed. Delta-V describes how the car's velocity changed in the crash, which depends on the mass and the angle of both vehicles.
• Short windows. If the record covers only a few seconds, it will not show how long a driver was distracted or drifting.
• No context. It does not say why a driver braked or whether a pedestrian stepped out. For that, you need witnesses, cameras and the scene. See dashcam footage and scene evidence: what to capture and keep.
• Driver-assist systems. A car with lane-keeping or adaptive cruise may record more or different items, and the question of who was driving can be central; see Driver-assist crashes: who pays when Autopilot-style features were on.

Preserving the data before the car disappears

Data can vanish in three ways: the module is overwritten by a later event, the car is repaired and the module replaced, or the car changes hands and goes to salvage. Taking a few steps early can keep the option open.

1. Tell your insurer and the adjuster in writing that you want the vehicle's data preserved. Name the vehicle by VIN, year and model.
2. Do not authorize the repair or disposal of the car until you decide whether to image the module. A body shop replacing the airbag module may discard the unit that holds the record.
3. If there is a dispute or an injury, consider asking a qualified technician to download and document the data now, with a report that identifies the tool and the person who made it. A lawyer can advise on who should do this, since a download may need the other side's notice.
4. Ask the insurer to hold the vehicle if it is a total loss and the data is contested. A total-loss car usually goes to a salvage auction after you are paid (total loss paperwork: titles, powers of attorney and release forms).
5. Remember the ownership rule. The Driver Privacy Act gives the data to the owner or lessee. When a total loss settles and the title transfers to the insurer, the owner changes, and with it your right to decide. Image the data before you sign the title if it matters to you.
6. Send a preservation letter to the other driver's insurer or the owner of the other vehicle if their car's data could help you. Courts can penalize a party who destroys relevant evidence after a lawsuit is reasonably foreseeable, but the rules vary, and that is a question for an attorney.

Questions to ask your insurer

• "Are you asking me to consent to a download of the event data recorder? Which tool, which technician, and who will see the report?"
• "Will you give me a copy of the report you obtain?"
• "If this car is a total loss, will you hold it for 30 days so I can arrange a download?"
• "Do you or your vendor use my telematics or connected-car data in this claim?"
• "Is my consent limited to this claim? Please put the scope in writing."

Common questions

Does my car have an event data recorder?

If it was made in recent years, probably yes. The owner's manual should say so, and the statement in the manual is required by the federal rule. Not every vehicle has one because the federal rule does not require installation.

Can my insurance company download my EDR data without my permission?

Under federal law and state laws such as California's and Texas's, an insurer generally needs the owner's consent or a court order. A policy may require you to cooperate with the investigation, so the question of whether to consent is worth discussing with the insurer and, if the claim is contested, a licensed attorney.

Can police read it after a crash?

In general, with the owner's consent or with a court order or warrant. Federal law also allows retrieval in a federal safety investigation and for emergency medical response. State law varies.

Key takeaways

• An EDR keeps a short crash record, typically speed, braking, throttle and belt status, and only when a crash crosses a trigger threshold; it does not record audio, video or a trip history.
• Under the Driver Privacy Act of 2015, the owner or lessee owns the data, and others can retrieve it only with consent, a court order, or a narrow exception such as a safety investigation or emergency response.
• State EDR laws, such as California Vehicle Code 9951 and Texas Transportation Code 547.615, add their own limits and differ, so check your state.
• Connected-car, infotainment and telematics data are separate from the EDR and are governed mainly by contracts and privacy law.
• If the data matters, ask in writing that it be preserved before repair, sale or salvage, and image it before the title leaves your hands; a licensed attorney can help when fault or serious injury is in dispute.