Crime is a set of acts defined as unacceptable by society. Acts of violence are often criminalized as well as certain types of property damage, fraud and embezzlement. Most societies punish crimes committed by individuals by severely restricting their freedom or imprisoning them if found guilty. Crime also encompasses violations of civil law and regulations. Anthropologists and sociologists have observed that definitions of what is considered criminal change over time, varying among cultures, social situations and specific contexts. Behaviors that are considered criminal often express what legal scholar Jerome Hall called “disvalues” and may be classified as offenses against the public good. Moreover, some behaviors that are deemed to be criminal may not constitute actual harm and are thus not subject to the same punitive penalties as other crimes. For example, a traffic violation or citation is not generally punished as seriously as first-degree murder.

Criminologists study the causes of crime, including what drives people to commit it. Forensic behavioral psychologists have long recognized that the motivation for crime can be complex, ranging from an individual’s need to gain power and status to peer pressure, the desire for financial gain and even a sense of dissatisfaction or boredom. In addition, sociologists study patterns of criminal activity and the role that community factors play in crime.

Other criminologists challenge the way that societal views about what is acceptable are translated into formal laws and prosecution. They question how interest groups control the symbolic meaning of laws and who gets to decide what is or is not a crime. For example, who defines what is a “principal in the first degree” (the perpetrator of an offense) and who qualifies as an “accessory before the fact” (those who aided, counseled or encouraged the crime’s commission but were not present at the actual moment of the perpetration).