Criminal Law defines and categorizes crimes and provides for the establishment of punishments for these crimes. In general, the law could categorize crimes as either felonies or misdemeanors based on their nature of the specific crime and the maximum punishment that could be imposed for it. The Criminal Law regards as felony a serious criminal misconduct which is punishable by death or by imprisonment for more than one year. As misdemeanor is considered an action that is punishable by imprisonment for less than one year.

Congress has the power of classifying certain conduct as a crime and determining the punishment for this crime in the Criminal Law and at the same time possess the right of revising them under certain circumstances.

State legislature has the power of passing a law that prohibits or punish any act providing that the law is not in contradiction with the provisions of United States or state constitution.

Laws that are passed by Congress or state must define the crimes and the punishments for them with certainty, because the citizens and the court system must have clear understanding of Criminal Law's requirements and prohibitions.

There are two major elements that are required by law for a person to be convicted in conducting a crime:

- overt criminal act - when a defendant purposely, knowingly or recklessly has done some act that is prohibited by law.

- criminal intent - when the defendant had a conscious objective to perform certain misconduct or cause a particular result.

There exist some possibilities when a crime act has resulted from the omission or failure to act of the defendant and in these cases the court has to judge over the specifications and the extend of negligent conduct of the defendant.