Factual ("but for") Causation:
Where a crime requires proof of a result (as opposed to an act), in order for the defendant to be convicted, the prosecution must prove that the defendant’s act was the legal cause of the result. For example:
Infuriated that Betty has married her ex-husband, Wilma takes a baseball bat and hides behind some bushes in front of Betty’s house. When Betty emerges, Wilma attacks Betty and kills her with the baseball bat. Although, in this case it will be relatively simple to do, the prosecution must prove that Wilma’s act resulted in Betty’s death in order to obtain a conviction.
In order to obtain a conviction, the prosecutor must prove both factual and proximate causation. In order to prove factual causation, the prosecutor must show that “but for” the defendant’s act, the result would not have happened as it did or when it did. Please note that the prosecution does not have to prove that the defendant’s action was the only thing that brought about the result. The defendant’s action may be one of several different actions and circumstances that contributed to the result. However, as long as the prosecutor can show that but for the defendant’s action, the result would not have come about as it did or when it did, the prosecutor has successfully proven factual causation, regardless of how many other actions and circumstances were involved in accomplishing the result. For example:
After coming out of her house one morning, Betty is attacked and beaten almost to death by Wilma. Jack Kavorkian is a well-respected physician who happens to be walking by and sees Betty lying in the street. Dr. Kavorkian examines Betty and knows for a medical certainty that Betty will die within the next few hours regardless of the medical attention she receives. Betty is in tremendous pain and Dr. Kavorkian decides to put her out of her misery. He pulls out his medical kit and injects Betty with some poison that he carries around in case of an emergency. In this case, although Betty would have died anyway, Dr. Kavorkian’s actions are the factual cause of Betty’s death. But for his actions, Betty’s death would not have come about when it did. Therefore, even though Dr. Kavorkian only sped up the inevitable, he can be convicted for Betty’s murder. See
People v. Ah Fat, 48 Cal. 61 (1874).
There are two exceptions to this “but for” rule. The first exception is where the result is brought about by two different factors operating concurrently, and either factor operating alone would have been enough to cause the result. In such a situation, each defendant’s action will be considered the factual cause of the result despite the fact that, if either defendant had not done what he did, the result would have been the same anyway. For example:
After emerging from her house one morning, Betty is attacked by Wilma and Barney. Wilma and Barney are both armed with baseball bats, and they proceed to beat Betty to death. In this situation, Betty’s death was brought about through Wilma and Barney’s concurrent actions. However, if their actions had not been concurrent, the result would have been the same. Had Wilma attacked Betty without Barney, Betty would have died when she did and how she did. And so, theoretically, Barney’s actions were not enough to establish "but for" causation. On the other hand, had Barney attacked Betty without Wilma, Betty would have died when she did and how she did as well and so, theoretically, Wilma’s actions are not enough to establish but for causation. However, because Wilma and Barney’s actions are concurrent sufficient causes, they will both be considered the factual cause of Betty’s death. See
Loggins v. State, 24 S.W. 409 (Tex. 1893) .
The second exception to the “but for” rule is where the chain of events that the defendant’s actions set in motion comes to rest in a position of apparent safety (in other words, it would appear to an observer that there is no longer a danger that the defendant's actions will cause the harm). If this happens, anything that occurs later as a result of the act will not be regarded as having been caused by the defendant. For example:
After leading the Boston Red Sox to their first World Series championship in eighty-five years, Ramon Garcia climbs to the fiftieth floor of the Prudential Center and throws the bat he used to get the game winning hit out the window. Luckily, the bat lands in a tree and nobody is hurt. A few hours later a stiff breeze blows the bat out of the tree. Unfortunately George is sitting under the tree when the bat falls. The bat hits George in the head, fracturing his skull, and George dies of his injuries a few days later. Had the bat hit George directly after Ramon threw it, Ramon’s action would have been considered the “but for” cause of George’s death. However, because the bat came to rest in a position of apparent safety in the tree, Ramon’s actions will not be considered the “but for” causation of George’s injuries. This is true in spite of the fact that, obviously, but for the fact that Ramon dropped the bat, George would not have died.
Even if the prosecutor can prove factual causation, he will not get a conviction unless he can prove proximate causation as well. Typically, proximate cause issues arise where an expected result comes about in an unexpected manner. The general rule is that the defendant’s actions will be regarded as the proximate cause of a result if the result occurred as a “natural and probable consequence” of the acts, and there was no intervening factor sufficient enough to break the chain of causation. See
Enraged that Betty has married her ex-husband, Wilma buys a gun and hides behind some bushes in front of Betty’s house. When Betty emerges, Wilma shoots Betty, hitting her in the arm. Betty turns and tries to run from Wilma, but in doing so she trips and hits her head on the sidewalk breaking her skull. Betty dies of her injuries a few minutes later. Although Wilma did not anticipate causing Betty’s death in this manner (Wilma might not have intended to cause Betty’s death at all), Betty’s death nevertheless was the natural and probable consequence of Wilma’s action (since it is natural for someone who is being shot at to try to run away) and since there were no intervening factors breaking the chain of causation, Wilma’s act will be considered the proximate cause of Betty’s death.
As we just mentioned, proximate cause will not attach if a superceding factor breaks the chain of causation between the defendant’s act and the result of the act. By definition, a superceding factor must be set in motion after the defendant has committed his act. Thus, a pre-existing condition cannot be a superceding factor and will not break the chain of causation. For example:
Wilma and Barney hatch a plan to kidnap Betty, drive her out into the middle of the desert and leave her there. As Betty is leaving her house one morning, Wilma drives up, Barney jumps out of the car, grabs Betty, stuffs her in the trunk, and then Wilma and Barney drive off. What Wilma and Barney don’t know is that Betty has a heart condition. As a result of the fright caused by Wilma and Barney’s actions, Betty suffers a heart attack and dies while still in the trunk of the car. In this case Betty’s heart condition is considered a pre-existing condition and, as such, it can not be considered a superceding factor that breaks the causation between Wilma and Barney’s act of kidnapping and Betty’s death. Therefore, the kidnapping is the proximate cause of Betty’s death.
Additionally, the intervening factor that breaks the chain of causation must be unforeseeable to the defendant at the time of his action. See
Wilma and Barney kidnap Betty, drive her to the middle of the desert, and leave her there. Betty manages to return home. However, she is severely dehydrated and sunburned by the time she returns. She is also suffering from a broken ankle which must be operated on. Unfortunately, the doctors at the hospital operate on the wrong leg. In this situation, Wilma and Barney’s actions will be considered the proximate cause of whatever Betty suffers as a result of the doctor’s negligence, because medical malpractice is considered a foreseeable intervening factor. However, had the doctors amputated Betty’s leg, when, clearly amputation was not required to fix the problem, Wilma and Barney’s actions would not be considered the proximate cause of the amputation because that would be considered gross negligence on the doctor’s part, and gross negligence is not considered foreseeable. See
State v. Clark, 248 A.2d 559 (N.J. 1968).
Intervening diseases contracted by the victim that are not directly related to the injury inflicted by the defendant are also not considered foreseeable. Therefore, had Betty contracted an illness unrelated to the broken ankle while in the hospital, Wilma and Barney’s actions would not be considered the proximate cause of Betty getting the illness (even though Wilma and Barney are the reasons that she is in the hospital). See
Finally, certain acts committed by the victim himself will be considered foreseeable. For example:
Betty escapes from Wilma and Barney and tries to run away from them. While running away, she runs across the street and gets hit by a car. Wilma and Barney’s actions will be considered the proximate cause of Betty’s injuries because a victim running away from her captors is considered a foreseeable response. However, if Betty successfully escapes and later, depressed because she's had a really bad week (being kidnapped and all), throws herself in front of an oncoming truck just to "end it all," this would be considered an unforeseeable act and Wilma and Barney would not be guilty of homicide.
Finally, in order to break the chain of causation, the intervening factor must be the sole and dominant cause of the result. If the intervening factor only combines with the effects of the victim’s conduct, they are considered concurrent proximate causes and the chain of proximate causation is not broken. For example: