¶ … Crime Actus Reus may be the most essential element involved in deciding what exactly makes up a crime. Most commonly defined as a voluntary act or an omission of an act, actus reus is one of the most objective elements in determining whether a crime has been committed since its result ( typically some form of injury to another or a group of people) is what largely comprises criminal activity. To fully understand the scope of actus reus, deliberate attention must be given to what exactly constitutes an act, or a criminal omission of an act.

In order for an actus reus to be linked to a crime it must be voluntary, meaning the accused must be aware of what is being done. An act can be any type of voluntary human behavior, and generally takes the form of some sort of physical movement which a person is conscious of. With such a widespread definition, there are limited circumstances in which an act may be deemed involuntary. Movements produced by muscles spasms are involuntary, as well as those made during a sleep-induced state or when a person is unconscious, which generally includes human behavior under the influence of hypnosis. Unless a body movement is made by a willful, determined effort from the actor, it cannot be considered a form of actus reus for criminal intentions. Interestingly, possession (of illegal material) is considered a voluntary act in the United States.

Omission of an act may also be included as part of actus reus, particularly when the negligence of an action results in injury to another. Criminal omission is largely determined by the "but for" principle, which states that a crime would not have taken place but for an act of omission. Certain laws explicitly state that omission of them constitutes a crime in their statutes, while failure to perform particular acts (which cause harm as a result of that failure) may also constitute an actus reus by omission.

Mens rea can be considered the psychological component of actus reus. While...

Although concurrence and casualty are important elements in labeling an act criminal or not, an actus reus combined with a mens rea -- meaning an established intent to injure or transgress law -- can typically determine an act of crime.
However, the severity of a crime and its culpability for the offender vary in terms of mens rea, which generally can be classified into four different categories. These stratifications not only factor into whether or not an act may be deemed criminal, but also play an import role in assessing punitive measures equitable to an infraction. The first type of mens rea is usually referred to as general intent. General intent is the most fundamental form of mens rea, which only requires the acussed to commit a crime. Premeditation or deliberately attempting to transgress law is not relevant to general intent, which only means the accused broke a law.

Specific intent is the form of mens rea that establishes that the accused was aware that his or her infraction was illegal. Specific intent is possibly one of the most severe forms of mens rea since it strongly indicates a willingness to commit crime. Its austerity is somewhat tempered by the more encompassing mens rea variety known as recklessness, which is used to describe a crime in which no regard was given to others in terms of the outcome of the action. Willful blindness bears some similarity to specific intent in establishing that a crime was willingly committed. It is the form of mens rea that declares the accused purposefully ignored the potential criminality of his or her act, so as not to know the result.

The concurrence element of a crime merely assists in establishing the timing of the mens rea in relation to the actus reus. In most cases, a mens rea must be established before or even during an actus reus to constitute that a crime has taken place. (One…