What Is the Cause of Most Car Accidents?

A man and woman examining a fender after a car accident.

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The causes of car accidents can seem endless. So many variables factor into accidents on the road. Determining what caused an accident is the responsibility of the police and the insurance company claims adjuster. The cause needs to be determined to determine who is at fault.

For the police, this is important because of legal liability and determining who should be issued a ticket. From an insurance company perspective, determining who is at-fault means determining which party, if any party, should receive a claim payment—and for determining how much that payment should be.

Human Error

A major source of car accidents is human error. The worst part is that we can only control our actions and not those of the driver next to us on the road. Careless drivers have caused accidents since the first car was built.

Distracted Driving

Driving while distracted seems to be on the increase with all the gizmos and technology gadgets built directly into vehicles and brought into vehicles. Cell phones, DVD players, and more are a relentless distraction for many drivers. Let alone kids, eating, and applying makeup. In our busy world, everyone wants to be multitasking at all times. The one place multi-tasking should be prohibited is behind the wheel.

Driving Under the Influence

Driving under the influence—whether it be the influence of drugs, alcohol, or even certain types of prescription and over the counter medicine—would be considered a human error. It is a bad choice made by many. Not being of a clear mind puts you at a much higher risk of being in or causing an accident.

Medical Conditions

Seizures, strokes, heart attacks, poor vision, or even falling asleep at the wheel can cause very serious accidents. Although medical conditions are often uncontrollable, it is important to think about your risk factors before driving. If you are not feeling well or forgot your glasses, definitely look for someone else to drive.

Being Lost or Not Knowing the Local Laws

Being unfamiliar with an area can be the cause of an accident, too. It is not impossible to get turned around or drive faster than what is recommended in an area you are unfamiliar with. Some people just flat out do not know how to drive. Not following the rules of the road puts a driver at higher risk of an accident, and not knowing the laws of a particular area is also a danger. In some states, for example, it’s forbidden to turn right at a red light, while in other states it is a-okay.

Mechanical Failure

Mechanical failure can happen for several different reasons. Sometimes it is out of control of the driver, and other times not.

Failure to Maintain Vehicle

Not doing normal upkeep on your vehicle can cause an accident. Bald tires, broken tie rods, and bad brakes are all things which need to be attended to in a timely manner. Imagine driving around on squealing brakes for a month then when you need them the brakes do not work at all. You really cannot blame the car. It was the car owner’s responsibility to maintain the vehicle.

Manufacturer Malfunction

Even though it is not all that common, sometimes accidents can occur because the car was not built properly. Automakers release recalls when a problem has been identified, but sometimes a recall only happens after several accidents have occurred. Be aware of recalls for your vehicle so you can have it repaired as soon as possible.

Faulty Traffic Lights

If a traffic light is out in the middle of the night, it can certainly be the cause of an accident. Someone unfamiliar with the area may not see the outage and run through an intersection. It is another example of mechanical error.


Even though the weather may be the cause of an accident, a driver is still held responsible when it comes to a single car insurance claim. Dense fog, excessive rain, slick roads, and high winds can all cause major problems for drivers. Even extreme differences in temperature can create large potholes worthy of damaging a car.


Animals do not understand the risk of crossing a road. When a large animal such as a deer goes to cross the road at a high speed, they can run right into the side of your vehicle. Hitting a deer head-on is also very common. The unpredictability of animals is what makes them so dangerous to drivers.

Driving is filled with perils. Drivers need to be on-guard 100% of the time. Autonomous cars could reduce human error in the future, but it is yet to be seen how it will impact car accidents.