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What Is Causation?

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What Is Causation?

Simple words often have complex meanings in a legal context. That’s true with causation. In simple terms, causation is when certain conduct or action makes something else happen.

If you’re riding your motorcycle and end up in a crash because a car ran a red light, the driver of the car caused your motorcycle accident. It’s fairly simple in that example, but many accidents are much more complex and may have multiple causes. If the traffic light was malfunctioning in that example, causation just got more complicated.

Even in an accident that’s fairly straightforward, you must prove causation to recover compensation for your injuries. In an injury case, proving causation means you have to show that the action or inaction of the at-fault party resulted in your injuries.

Two Types of Causation

Two Types of Causation

While you may not ever talk about this with your personal injury attorney or hear it in court, there are two main types of causation: (1) actual cause; and (2) proximate cause. You must prove both to establish causation. To make things more confusing, the terms often overlap. Many states combine the concepts when analyzing causation.

Actual Cause

Actual cause is the action or conduct that is the reason for a subsequent consequence. Actual cause is generally established by looking at the action immediately preceding the accident. In a personal injury context, if the plaintiff’s injury would not have occurred “but-for” the defendant’s actions, then the defendant’s actions are the actual cause of the plaintiff’s injuries.  

If a car hits a pedestrian in a crosswalk, the driver of the car is the actual cause of the pedestrian’s injuries. However, the immediate preceding cause may not answer the legal question of who is liable for an accident.

Proximate Cause

Proximate cause is the legal cause of a particular result. The concept of proximate cause is not as clear as actual cause. Establishing proximate cause is a way to integrate foreseeability into a defendant’s actions. A defendant may be held liable for results that are reasonably expected to result from their actions, but not damages that are too far removed from their actions. 

California has adopted the “substantial factor” test when determining proximate cause. California courts have explained that the “but-for” test is basically included in the “substantial factor” test. If the defendant’s action (or inaction) was a substantial factor in bringing about the plaintiff’s injuries, the defendant can be held liable for the plaintiff’s damages.

Suppose the car hit the pedestrian in the above example because the brakes failed. Were the brakes defective? Or did the owner not keep up with car maintenance? Or did the maintenance shop lie about replacing the brakes? You can see how proximate cause can get complicated. Careful investigation and analysis from experts is often required in complex cases.

How Does Causation Affect My Personal Injury Case?

In a personal injury context, causation is the key to your case. That’s because most personal injury cases are based on negligence, and causation is a legal element of negligence. 

Negligence is a legal theory that allows an injured party (the plaintiff) to hold another party (the defendant) financially responsible for damages caused by failing to act reasonably under the circumstances.

But to do so, the plaintiff must prove:

  • The defendant owed the plaintiff a legal duty of care
  • The defendant’s actions or omissions constituted a breach of the duty owed to the plaintiff
  • The defendant’s actions caused harm to the plaintiff
  • The plaintiff suffered actual damages as a result of the defendant’s conduct

Without proving causation, you won’t be able to show that you’re entitled to damages for your injuries.

How Do I Prove Causation?

Proving causation in a personal injury lawsuit is done by presenting evidence. In many personal injury cases, you may not ever end up going to court – and that’s usually because the insurance company knows that you have the evidence to prove your case.

Some types of evidence used to prove causation could include:

  • Eyewitness testimony or testimony of the parties
  • Video footage from traffic, security, or dashboard cameras
  • Medical reports
  • Toxicology reports
  • Testimony and reports from experts such as engineers, medical examiners, and accident reconstructionists

Personal injury lawyers will conduct an independent investigation of your accident to determine the cause. Often, more than one party is responsible.

What If I Was Partly Responsible for the Accident?

In California, if you’re partially at fault for the accident in some way, then your damages will be reduced by the portion of the accident caused by your own negligence. That’s because California uses a pure comparative negligence rule when evaluating the plaintiff’s role in the accident. 

A common tactic of insurance companies is to blame the victim – if they’re successful in proving that you’re responsible, they won’t have to pay your claim. An experienced attorney will protect you from unfair blame as they work to prove that the defendant caused your injuries.