# What's Causation and How Do I Prove It? | Attorney Brian White **Table of Contents***[*Expand*]* 1. Defining Causation 2. Understanding the Two Types of Causation 3. How Courts Determine Actual Causation 4. Proving Proximate Causation in Personal Injury Cases ![What’s Causation and How Do I Prove It?](https://attorneybrianwhite.com/wp-content/uploads/2021/04/what-is-causation-and-how-do-i-prove-it-300x200.jpg) During rush hour, a car races through a [red light](https://attorneybrianwhite.com/houston-tx/car-accident-lawyer/red-and-yellow-light/) and plows into two other vehicles. As the first car comes to an abrupt stop in the middle of the intersection, another car runs into its [rear end](https://attorneybrianwhite.com/houston-tx/car-accident-lawyer/rear-end-collision/). Meanwhile, the other two vehicles strike two pedestrians and a biker.  Who caused the [car accident](https://attorneybrianwhite.com/houston-tx/car-accident-lawyer/) and the injuries to the [pedestrians](https://attorneybrianwhite.com/houston-tx/pedestrian-accident-lawyer/) and the [biker](https://attorneybrianwhite.com/houston-tx/bicycle-accident-lawyer/)? What about the other cars’ drivers? While it may seem easy to prove who caused the injuries, in this case, proving causation in court could be a complicated process.  ## Defining Causation ![Defining Causation](https://attorneybrianwhite.com/wp-content/uploads/2021/04/defining-causation-300x200.jpg) Causation generally refers to one thing that is a catalyst for something else. Though the legal definition is similar, causation can be slightly more complicated in court cases. In law, causation is a critical element that a [plaintiff](https://attorneybrianwhite.com/faqs/who-are-plaintiffs-and-defendants-in-a-personal-injury-case/) must prove to show negligence in a personal injury case. The [legal definition of causation](https://definitions.uslegal.com/c/causation/) is the cause and effect relationship between one party’s injury-causing conduct and the damages another party claims in a personal injury case.  For a legal consultation call [(713) 500-5000](tel:+17135005000) ## Understanding the Two Types of Causation ![Understanding the Two Types of Causation](https://attorneybrianwhite.com/wp-content/uploads/2021/04/understanding-the-two-types-of-causation-300x169.jpg) Before you can prove causation, it’s necessary to understand that most courts, including Texas courts, break down causation into two categories: actual cause and proximate cause. Plaintiffs must prove both types to win their case. The first type, “cause in fact,” also known as the actual cause, is the simplest. For example, car A runs into car B. Driver A’s actions are the actual cause of the accident. The [proximate cause](https://www.law.cornell.edu/wex/proximate_cause), also known as the legal cause, is often more complicated. Courts consider the series of events that led to the plaintiff’s injury. The defendant’s conduct is the proximate cause of the plaintiff’s injuries if the injuries were reasonably foreseeable. To make things even trickier, some situations don’t have a proximate cause at all. Other cases have overlaps between the proximate and actual cause.  ## How Courts Determine Actual Causation As noted above, the actual cause is generally clear-cut. Proximate cause gets trickier. The courts rely on tests to make a determination of cause. ### The But-For Test For actual cause, many states use the [but-for test](https://www.law.cornell.edu/wex/but-for_test). In personal injury cases, the but-for test asks, “would the plaintiff have been injured ‘but for’ the defendant’s actions (or inactions)?” For example, Driver A drove through a red light into a busy intersection and struck Driver B, who sustained whiplash. But for A hitting B, Driver B would not have suffered whiplash. It’s important to note that by driving into a busy intersection, it should have been foreseeable to Driver A that they would likely hit one or more cars. Accordingly, Driver A’s actions are the proximate cause of B’s injuries also. It’s easy to see how complex these situations can get, especially when there is a long string of events involved and multiple parties. Additionally, the but-for test can be problematic as people tease out too many relations between actions. ### The Substantial Factor Test Another common test asks whether or not the defendant’s actions (or inactions) played a substantial role in causing the plaintiff’s injuries. In this approach, trivial actions or failures to act may not be enough to establish actual causation. Consider the above example where Driver A struck B. It’s easy to see that A’s recklessness at running the red light into a busy intersection was a substantial factor in the accident. However, the scenario could change if Driver B contributed to the outcome of the accident. [Click to contact](/contact-us/) us today ## Proving Proximate Causation in Personal Injury Cases Knowing how the court views proximate cause is part of the equation. Proximate cause is concerned with fairness and limiting the chain of events for which the plaintiff can claim causation.  Tests for actual cause often implicate persons or events that are only remotely connected to the accident, and for which it would be unfair to hold them liable. For example, “but for a car dealership selling Driver A their car, Driver B would not have been injured. Proximate cause prevents the plaintiff from suing parties whose actions are too remote to hold them liable fairly. It does this by only making a defendant liable for the foreseeable injuries they cause to foreseeable plaintiffs. Say Driver A ran a red light and hit Driver B. This time, Driver B spins out and hits Driver C. Was it foreseeable that Driver A would strike at least one car if they sped through a red light at a busy intersection? Yes, a reasonable person would have predicted the likelihood of an accident.  Driver A would also likely be liable for Driver C’s injuries under a proximate cause analysis. Even though Driver B actually collided with Driver C, Driver A’s actions were the proximate cause of Driver C’s accident and injuries. It was foreseeable that Driver A’s running through a red light might cause a collision with another driver (Driver B) who might also collide with a third driver (Driver C). It’s easy to see how complicated causation can be, and defendants are likely to toss out any [mitigating](https://attorneybrianwhite.com/faqs/what-does-it-mean-to-mitigate-damages/) factors to offset their culpability. If you’re facing a personal injury case, it may be in your best interest to consult with a knowledgeable lawyer at [Attorney Brian White Personal Injury Lawyers](https://attorneybrianwhite.com/) who can guide you through the process. [Contact](https://attorneybrianwhite.com/contact-us/) our Houston personal injury law office to get started today, or call us at [(713) 500-5000](tel:+17135005000). Call or Text [(713) 500-5000](tel:+17135005000) or Complete a [Case Evaluation Form](/contact-us/) Personal Injury Blog Posts: [![Dealing With Grief: A Step-By-Step Guide for Emotional Healing After the Unexpected Death of a Loved One](https://attorneybrianwhite.com/wp-content/uploads/2023/01/Dealing-With-Grief-A-Step-By-Step-Guide-for-Emotional-Healing-After-the-Unexpected-Death-of-a-Loved-One-300x200.jpg)](https://attorneybrianwhite.com/blog/dealing-with-grief-a-step-by-step-guide-for-emotional-healing-after-the-unexpected-death-of-a-loved-one/) [Dealing With Grief: A Step-by-Step Guide for Emotional Healing After the Unexpected Death of a Loved One](https://attorneybrianwhite.com/blog/dealing-with-grief-a-step-by-step-guide-for-emotional-healing-after-the-unexpected-death-of-a-loved-one/) When you experience loss, you will go through a process called grieving. 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