Texas courts break down causation into two types: actual and proximate. Generally a plaintiff must prove both types to win a case.

Actual cause is fairly straightforward. Suppose the defendant is texting while driving, and rearends the plaintiff. The defendant’s actions are the actual cause of the accident. 

Proximate cause is usually more complex, and considers the series of events that led to the plaintiff’s injury.

In the example above, the defendant’s actions could be reasonably foreseen to lead to the plaintiff’s injury, so they are the proximate cause of those injuries.

To add further complexity, imagine the plaintiff’s seat belt malfunctions, and the accident would not have resulted in injury ‘but-for’ that malfunction. This might result in some or even all of the liability falling on the automobile manufacturer.