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Actus Reus

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Actus Reus:
“Guilty Act”
, the wrongful deed that comprises the physical component of a crime and is a prerequisite to establishing criminal liability.  An “Act” must be coupled with a “mental state” (“mens rea”) to establish criminal liability.

Something done or performed, whether voluntary or involuntary.

Mens Rea:  
“guilty mind”, the state of mind that the prosecution, to secure a conviction, must prove that a Defendant had when committing a crime; For example, criminal intent or recklessness.  (Further discussion of mens rea will follow in the following chapters but for purposes of clarification it has been defined here).

A failure to do something; a neglect of a duty.

In order to be convicted of a crime, a defendant must have committed an "actus reus," or criminal act. Under some circumstances, a defendant can be convicted of committing a crime for failing to act as well (an "omission"). Either way, the basic principles of criminal law always define crimes in terms of acts. The reason for this is that we do not punish people simply for their thoughts or intentions. Further, by virtue of the Eighth Amendment Ban on Cruel and Unusual Punishment we do not define crimes in terms of status either. For example:

The State Legislature has recently passed a law making it a crime to be an alcoholic. This statute is unconstitutional because it criminalizes a status rather than an act or omission. If, however, the Legislature had passed a law making it a crime to appear in public while drunk, this would be fine. This law would be criminalizing a particular act, not a mere status. See Robinson v. California, 370 U.S. 660 (1962)

Different crimes are defined by different acts. Certain crimes are defined in terms of specific acts that the defendant must have committed. In such a case, in order to convict a defendant of committing one of these crimes, the prosecutor must prove that the defendant committed each specific act. For example, as we will see later, the crime of burglary is defined as "the breaking and entering into someone else’s dwelling at night with the intent of committing a felony." Therefore, if a defendant is on trial for burglary, the prosecution will have to prove that the defendant broke into another person’s dwelling, that he entered the dwelling,that he did so at night and that he intended to commit a felony therein. If the prosecution fails to prove even one of these elements, the defendant will be acquitted.

However, other crimes are defined by more general acts. In these situations, a conviction can be based on proof that the defendant committed the general act constituting the crime. For example, homicide is defined as the killing of another human being. As you can see, homicide is not defined in terms of any particular act of killing. That being the case, the prosecution does not have to prove that the defendant killed the victim with any particular act (ex. shooting or stabbing, etc.). Rather, a defendant charged with homicide will be convicted if the prosecution proves that the defendant committed, with the requisite intent, a volitional act that resulted in the victim’s death.

In either case, all acts must meet certain requirements. For example, where criminal liability is based on an affirmative act, which is usually the case, the prosecution must show that the defendant made a conscious and volitional movement. See State v. Mercer, 165 S.E.2d 328 (N.C. 1969). Acts that are done by a person due to mere reflexes, convulsions or movements made while the defendant is sleeping or otherwise unconscious do not meet the legal definition of an act because they are not volitional. For example: 

Fred is a sleepwalker. One night during a particularly vivid dream in which Fred is being chased by his friend Barney, Fred takes the gun that he keeps on his bedside table, goes to Barney’s house and shoots Barney. Fred wakes up in the police station, having no idea why he is there or how he got there. In this instance, Fred’s act will not support a conviction because he was unconscious at the time he was acting. Therefore, his acts do not satisfy the actus reus element that is inherent in all crimes.

However, if the defendant was at fault for bringing about his state of unconsciousness, he will be responsible for the acts he commits while unconscious. For example:

One night Jack Daniels and his friend Jim Beam decide to go out and have a few drinks. Jack has a few too many, and drinks himself into a state of oblivion. While in this state of unconsciousness, Jack hits Jim over the head with a bar stool crushing Jim’s skull and killing him instantly. In this case, although Jack’s actions were committed while he was in a state of unconsciousness, his acts will nevertheless support a conviction for homicide because he was at fault for drinking to the point of unconsciousness. Of course, the severity of his homicide conviction and sentence will not be as great as it would be if the act were a premeditated murder, but there is enough to sustain a homicide conviction. See Watkins v. People, 408 P.2d 425 (Colo. 1965).

In addition, a person can be found criminally liable if he engages in a course of action knowing that he may unintentionally become unconscious and hurt somebody while he is engaging in that course of action. For example:

Rip has recently been diagnosed with narcolepsy, a rare disorder in which a person instantly and suddenly falls asleep. Despite knowing that he could fall asleep at any time, Rip decides to take his new sports car out for a spin. While driving along a crowded street, Rip falls asleep. His car veers off the road and plows into a crowd of people. As a result, three people are killed. In this case, Rip can be convicted for the deaths of those three people because, although he was unconscious at the time he ran those people over, Rip knew that he could become unconscious and potentially hurt people when he started to drive the car in the first place. See People v. Decina 2 N.Y.2d 133 (1956).

As we mentioned before, under certain circumstances, criminal liability can be based on a defendant’s failure to act. However, in order to sustain a conviction based on a mere failure to act, the prosecution must prove that 1) the defendant was under a legal duty to act; 2) the defendant knew that he needed to act; and 3) it was possible for the defendant to act. For example:

  1. Hooper is sitting in his rowboat out in the middle of a lake. Martin is swimming in the lake and begins to drown. Martin is about fifty feet from Hooper’s boat and Hooper neither sees nor hears Martin, and Martin drowns. In this case, even assuming that Hooper had a legal duty to try and save Martin, the prosecution could not convict him based on his failure to act because Hooper did not know that he needed to act. Since Hooper had no idea that Martin was in distress his lack of action will not bring a criminal conviction.
  2. Hooper is sitting in his rowboat in the middle of the lake. Martin is swimming in the lake and begins to drown. Martin is about fifty feet from Hooper’s boat, but Hooper cannot make his way over to Martin because his oars have fallen into the water and floated away. Hooper is also a very poor swimmer. Martin drowns. Again, even assuming that Hooper had the legal duty to act in this situation, the prosecution will not be able to convict him for Martin’s death because although Hooper knew he needed to act, it was impossible for him to do so. That being the case, Hooper’s inaction will not bring criminal liability.

At common law the general rule in both civil and criminal law is that there is no duty to act in order to protect or rescue another person. However, as far as criminal law is concerned, there are five instances under which a failure to act may result in criminal prosecution. First, if the defendant has a special relationship to the victim, he may have a duty to act in certain situations. The special relationships that establish the duty to act are parent/child relationships, husband/wife relationships and employer/employee relationships. Second, there are statutory duties to act. In other words, certain states have passed statutes requiring a person to act and failure to do so will result in criminal prosecution. Third, a private contract between two parties can generate a duty to act. This is usually the case in situations where the defendant was under a contractual duty to protect or care for someone else. See Commonwealth vs. Pestinikas, 617 A.2d 1339 (Pa. 1992). For example:

Whitney is a famous pop singer who hires Kevin to be her bodyguard. Kevin is contractually bound to escort Whitney while she is in public and to come to her aid if the need ever arises. One day while walking in public, Whitney is mobbed by a group of fans. Kevin doesn’t feel like interfering so he lets the fans crowd around Whitney. One of the fans punches Whitney and steals the diamond necklace she is wearing. In this situation Kevin may be criminally prosecuted because he was contractually bound to come to Whitney’s aid, and he failed to do so. 

The fourth instance where the failure to act can result in criminal prosecution is where the defendant had no legal obligation to aid the victim but he voluntarily undertook to aid the victim. In this situation, if the defendant abandons his rescue efforts and thereby leaves the victim in a condition that was worse than he would have been in had the defendant not started to help at all, the defendant can be criminally liable. For example:

Whitney is swimming in a lake when she begins to drown. Kevin sees her drowning and jumps into a boat and begins to row out to her. There are several people on shore who would have gone out to help Whitney. However, when they see Kevin going to help they stay on shore. For some reason, Kevin changes his mind about helping Whitney and turns around and rows back to shore. Whitney drowns. In this situation Kevin can be criminally liable for Whitney’s death. Although he did not have the legal obligation to go to her aid, he voluntarily undertook to help her and his failure to follow through with his rescue effort left Whitney in a worse position than she would have been in had Kevin not done anything in the first place.

Finally, a defendant will have the duty to aid another person if he wrongfully placed the victim in harm’s way to begin with. In this situation, failure to help the victim can result in criminal liability. 

For better or for worse, the law still does not impose criminal liability for an omission to act where the defendant had nothing more than a moral duty to act. See People v. Beardsley, 113 N.W. 1128 (Mich. 1907). For example: 

Lyle and Eric decide to spend a few days gambling in Las Vegas. At one point during their first night at the casino, Lyle excuses himself to use the men’s room. On his way to the men’s room he lures a little girl into going with him. Once they are in the men’s room, Lyle attacks the little girl and starts strangling her. Eric walks into the men’s room and sees his friend strangling the little girl, but does nothing to stop it. Lyle ends up killing the little girl. In this situation, Eric cannot be criminally prosecuted for failing to help the little girl. Although Eric is a moral monster for what he did, he was under no legal duty to come to the little girl’s aid, and he therefore cannot be prosecuted.

As we mentioned previously, a defendant who has the legal duty to act and fails to do so will not be prosecuted if he did not know that his action was needed. For example:

Hooper is sitting in his rowboat out in the middle of a lake. Martin is swimming in the lake and begins to drown. Martin is about fifty feet from Hooper’s boat and Hooper neither sees nor hears Martin, and Martin drowns. 

As we said before, even assuming that Hooper had a legal duty to try and save Martin, Hooper cannot be held criminally liable based on this failure to act because Hooper did not know that he needed to act. However, what would happen in a situation where Hooper knew that Martin was in trouble but did not go to Martin’s aid because he did not know that the law required him to do so?

Usually, the defendant can still be prosecuted for failing to act even if he did not know that the law required him to act. This follows the general principle that "ignorance of the law is no excuse." Nevertheless, if the law requiring a person to act says that only the “willful” failure to act is a crime, then the defendant’s ignorance of the law will protect him from prosecution. For example:

The town of Amity has passed a law saying that “any person who willfully fails to go to the aid of someone who is drowning will face criminal prosecution”. Hooper is sitting in a boat in the middle of the lake. Martin is swimming in the lake when he begins to drown. Hooper sees Martin drowning but does nothing to help him. Hooper is unaware that there is a law requiring him to go to Martin’s aid. In this situation, all three requirements for criminalizing a failure to act are present. Hooper has a statutory duty to come to Martin’s aid. He is aware that Martin needs his help, and it is possible for him to help. Nevertheless, in this situation, Hooper will probably escape prosecution because the law prohibits the willful failure to act, and the court may hold that the willful failure to act can only come about if the defendant knew the law. Here, Hooper did not know the law, and so he did not willfully break the law. On the other hand, had the statute simply criminalized the failure to act when someone was drowning without using the word "willfully," then Hooper would be in violation of the law and could be criminally prosecuted for it even though he did not know what the law was.

Finally, as we mentioned before, a defendant who has a legal duty to act and who is aware that his action is required will nevertheless be insulated from prosecution if it was not possible for him to act. In other words, the defendant will not face criminal prosecution in a situation where his failure to act was due to the fact that he lacked either the means or the ability to perform. 

However, please note that even if a defendant is incapable of acting on his own, he can be prosecuted if it was reasonably possible for him to get other people to help the victim but failed to do so. See Stehr vs. State, 139 N.W. 676 (Neb. 1913). For example:

Hooper is a paraplegic. One day he rolls his wheelchair out onto the dock so that he can enjoy the breeze coming in off the lake. While sitting on the dock, he sees Martin swimming out to the middle of the lake. Martin begins to drown. Obviously it is impossible for Hooper to come to Martin’s aid, but Hooper could have gone to find other people to help Martin. However, Hooper just sits there and watches Martin drown. In this situation, since Hooper could have gone and gotten other people, and failed to do so, he can be criminally prosecuted for Martin’s death. (assuming that, for whatever reason, he had a duty to act.)