Common Causes of Semi Truck Accidents

Each year, thousands of semi-truck accidents occur throughout California. As large vehicles, they have the potential to inflict significant harm on anyone involved. This is especially true when the other vehicle is small.

Like most accidents, those involving semi-trucks occur for a number of reasons. Some causes will identify the driver as being negligent. By understanding more about them, it’s possible to determine negligence and reduce the risk of future incidents.

Common causes of semi-truck accidents

Like other vehicles, semi-trucks are vulnerable to dangerous driving practices and human error. Because of their size, they’re also vulnerable to unique crash causes.


All drivers pose risks when they allow themselves to be distracted. The risk of harm is even greater when you’re behind the wheel of a semi-truck. Using a phone while driving a large vehicle means that the driver isn’t in control of the truck. Additionally, choosing to adjust a GPS system while driving rather than stopping in a safe place is dangerous. Other distractions, such as talking to another passenger or looking at something on the side of the road, aren’t as easy to prove in a personal injury case.

Poor training

The handling techniques required to drive a semi-truck are more challenging than those required to drive a car. Unfortunately, haulage companies may rush their drivers through training to get them on the road faster. It’s a common cost-saving technique, but it has fatal consequences. Drivers who aren’t experienced in meeting the challenges of different roads have a bigger risk of crashing. Additionally, poor training makes drivers underconfident, which may result in slower decision making.

Drugs, Alcohol, and Medication

No driver should operate a vehicle while under the influence of drugs and alcohol. Some drivers may operate their vehicle without realizing their Blood Alcohol Concentration (BAC) levels are still high. This usually happens when someone has consumed a lot of alcohol the night before driving and wakes up believing they’re able to drive.

Some types of medication are safe to drive on. A small number are not. Medications such as benzodiazepines and hypnotics can take hours to leave a driver’s system. Although they’re excellent for battling insomnia, they also slow down reaction times. As a result, they increase the chances of a semi-truck accident happening.

Certain over-the-counter medications can make a semi-truck driver ill-fit to drive too. For example, anti-sickness medications or drowsy anti-histamines. If drivers fail to read the instructions or they choose to ignore them, they may drive while feeling drowsy. This means they’re at risk of missing the warning signs of an accident that’s about to happen.


Driving following a poor night of sleep can be as dangerous as driving while under the influence of alcohol. Semi-truck drivers are particularly vulnerable to fatigue because they spend a lot of time behind the wheel. Additionally, they often work abnormal hours, which makes maintaining a routine sleeping pattern difficult.

To reduce the risk of fatigue causing an accident, federal regulations identify how long a driver can work for and how often they need to take a break. Despite this, some drivers may continue working, especially if they’re paid per mile. In some cases, drivers may follow their break recommendations, but they might struggle to rest and will go on to cause an accident as a result.

Speeding and overtaking

Drivers who depend on a per-mile wage may find themselves speeding and overtaking on the road. Going faster and overtaking vehicles that are driving slowly can help them squeeze more miles into their legally-permitted work times. As semi-trucks don’t accelerate as fast as other vehicles, overtaking is particularly hazardous. Some of the most dangerous semi-truck accidents involve head-on collisions, which are more likely to happen in poor overtaking conditions. Additionally, drivers who find themselves heading toward an overtaking semi-truck may veer off the road and crash to avoid a collision.

When driving at a higher speed, semi-truck drivers have less time to react to dangerous situations. If speed is combined with factors such as fatigue, the risk of a semi-truck accident rises even further.

Unrealistic Schedules

Even if a truck driver doesn’t receive per-mile compensation, they may find themselves operating on an unrealistic schedule. Their employers may state that they need to reach certain destinations at particular times. Unfortunately, tight schedules don’t make allowances for incidents such as heavy traffic or accidents. If a driver is delayed, they may start rushing or skipping breaks, which then increases their risk of causing a semi-truck accident.

Poor Maintenance

Semi-trucks cover thousands of miles over a matter of days. Because of this, they require more regular maintenance than other types of vehicles. It also means that vehicle parts start declining faster than they do in cars. For example, tires will lose their tread faster and when they fall below an acceptable level they won’t allow for normal braking times. Federal regulations outline the condition that a semi-truck must be in for someone to drive it. If there’s an accident and a report finds that the truck was in a state of disrepair, either the fleet owner or the driver may be negligent. Cases involving poor maintenance will focus on whoever owns the vehicle and has a legal responsibility to maintain it.

Poor Loading

One way to reduce the risk of a semi-truck accident is to use correct loading. The vehicle’s manufacturer will provide recommendations on how to distribute weight. Additionally, those recommendations will identify how much weight the truck can safely carry. Unfortunately, packers aren’t always familiar with the loading recommendations for every truck. Improper loading can affect stopping distances and vehicle control.

Reduced Visibility

Unlike everyday vehicle drivers, semi-truck drivers struggle to see the cars that are behind or to the side of them. Some trucks may feature signs that warn other drivers of this and advise them not to drive too close so the truck driver can see them. If other road users ignore this warning, they’ll find themselves driving in a ‘no zone’. As a result, the semi-truck driver won’t be aware of their presence.

Other Road User Causes

It would be unfair to assume that all semi-truck accidents arise as a result of the truck driver. Other road users engage in dangerous actions too, which can cause or contribute to crashes. Such causes could result in comparative negligence, which has the power to diminish or eliminate a claim.

Abrupt Lane Changes

When driving on a highway, drivers often swerve into other lanes so they can overtake slower vehicles. If they do this abruptly in front of a semi-truck, they may cause its driver to hit the brakes. Additionally, if they do so and then fail to accelerate, the truck may crash into them.

Misjudging Speed

When approaching an intersection, it’s often tempting to make a quick left turn. Drivers who do this while misjudging an oncoming truck’s speed are at risk of crashing. Even if the semi-truck accident doesn’t directly involve their vehicle, the truck driver’s sudden stop may derail vehicles behind them.

Poor Merging Response

Semi-truck drivers need to merge onto highways and change lanes too. An appropriate response to this is usually to slow down. In some cases, it’s safe to speed up enough to give the truck space to reach the road safely. Vehicle drivers may not notice the truck or they may choose not to allow it into their lane. Unfortunately, if the driver needs to merge, a semi-truck accident may happen.


Some semi-trucks are large enough to produce crosswinds that affect smaller vehicles. When attempting to pass by a truck, drivers need to remain mindful of their vehicle handling. If they subsequently swerve into another lane, an accident could happen. Additionally, if their vehicle is poorly maintained and its tracking is not balanced, they may struggle to maintain their usual control.

Overtaking a Truck

Overtaking a semi-truck on smaller roads is usually unwise. It’s difficult to judge how long it will take for an oncoming vehicle to reach the overtaking one. Additionally, visibility isn’t usually good enough to avoid hazards, especially when overtaking on a bend or corner. As such, drivers should limit overtaking to larger roads, such as highways.

Pulling Out

Most drivers will find themselves pulling out in front of a semi-truck at some stage. However, it’s important to only do so when there’s sufficient room. Additionally, drivers need to be confident that they can accelerate quickly enough to prevent the truck driver from hitting their brakes. Semi-trucks have slower stopping times than smaller vehicles, so hitting the brakes may be less effective for them than it is for others.

Consequences of Semi-Truck Accidents

While the average passenger car weighs 4,000 lbs, the average semi-truck vehicle can reach over 80,000 lbs. In a collision, this can result in near-fatal or fatal consequences for the smaller vehicle’s driver.

In 2017, the number of large truck accident fatalities rose by 9 percent. Over 4,700 people died and 70 percent of those individuals were in the other vehicle. Of the truck drivers that died, 40 percent weren’t wearing seatbelts.

In non-fatal semi-truck accidents, those involved may suffer from long-term disabilities. Damage to limbs and spinal cord damage can result in significant medical bills. Some individuals require lifelong medical care, as well as ongoing therapy to hasten their recovery. In the most tragic cases, victims of semi-truck accidents may find themselves unable to work. As a result, they face a significant loss of earnings and a reduction in their quality of life.

Being involved in a semi-truck accident is undoubtedly a terrifying event. Mental consequences such as Post-Traumatic Stress Disorder (PTSD), depression, and anxiety are common. The mental anguish a driver or passenger can suffer following an accident is often difficult to manage.

Determining Who Is Responsible

Most semi-trucks don’t belong to the individual driving them. Although the driver is a likely defendant when a semi-truck accident occurs, other people and organizations may be to blame too.

Drivers who are operating according to an unrealistic schedule may share the blame for an accident with the organization they’re working for. This is especially true when there’s evidence of the organization promoting unsafe working practices. In a small number of cases, government officials may also be held responsible. This may happen when the road is found to be unsafe and relevant officials were aware of the need to address the problem.

When filing a claim following a semi-truck accident, it’s important to determine who’s responsible early into the proceedings. If someone shares blame, it may become impossible to add them into the case once proceedings are underway. Other parties that could be to blame include loaders, maintenance teams, and mechanics. By failing to file a claim against the right persons or bodies, it’s difficult to access the right amount of compensation.

Gathering Evidence

When filing a claim following a semi-truck accident, it’s essential to gather evidence. Courts and insurance companies usually expect to see the following:

Medical Reports

You’ll need comprehensive medical reports detailing the injuries and predicted health outcomes. This could include diagnostic images and their associated reports, medical notes, and treatment plans.

In cases involving mental anguish, it isn’t strictly necessary to produce a counselor’s report. However, any claims surrounding mental anguish are far more likely to succeed when such reports are available.

Mechanic’s Reports

It’s useful to get the mechanic’s reports that pertain to all vehicles involved. Poor vehicle maintenance can contribute to stopping times and a lack of control. In addition to the mechanic’s reports from before the accident, courts expect to see those from after the accident. It’s important to retrieve such reports in a timely manner, otherwise legal teams may question their legitimacy.


Semi-truck accidents are often too severe for the drivers to take photos. However, if it’s possible to do so, capturing images at the scene can make a big difference to the outcome of a case. It’s important not to delay accessing essential medical care in order to do this. Additionally, if the accident scene is dangerous, don’t go near the vehicles in an attempt to take photos.

Legal Assistance

If you’re involved in a semi-truck accident, it’s important to seek legal assistance. Your personal injury lawyer can gather evidence and fight your claim while seeking the compensation you deserve. At Quirk Law Group, we assist our clients with semi-truck accidents throughout Los Angeles and Thousand Oaks. To receive the legal support you deserve, call 866 306 9106.