Section 1.3: Defining and Measuring Crime

A banner reading "Criminal Justice: An Overview of the System" by Adam J. McKee

In the criminal justice system, a crime is an act or omission that is prohibited by law. This means there are specific actions or behaviors that the government has deemed unacceptable and has created laws to restrict them. When a person commits a crime, they are considered to have failed in their duty to the community, and the community will exact some punishment in response.

Video Overview

Video Overviews of Section 1.3 are available on YouTube:

Reading Time: 10 minutes

The most common punishments for crimes in the United States are fines and imprisonment. Fines are monetary penalties that a person must pay for committing a crime, while imprisonment involves being confined in a correctional facility for a certain period. The severity of the punishment typically depends on the seriousness of the crime and the specific laws that have been broken.

Legal scholars have historically distinguished between two types of crimes: mala in se and mala prohibita offenses. Mala in se offenses are considered “wrongs in themselves,” meaning they are inherently immoral or unethical. Examples of mala in se offenses include murder, rape, and theft.

In contrast, mala prohibita offenses are acts that are considered criminal only because the government has made them illegal. Examples of mala prohibita offenses include traffic violations, drug possession, and gambling.

While this distinction may seem straightforward, it is essential to note that there is an ongoing debate about whether certain crimes should be considered mala in se or mala prohibita offenses. For example, some argue that drug possession should be viewed as a victimless crime and, thus, a mala prohibita offense. In contrast, others believe drug use is inherently harmful and should be classified as a mala in se offense.

Felonies, Misdemeanors, and Violations

Today, the criminal justice system divides crimes based on their seriousness and potential punishments. Misdemeanors are less serious crimes punishable by confinement in a local jail for up to a year or a fine. Felonies are more serious crimes, punishable by fines, imprisonment exceeding a year, or death. The distinction between misdemeanors and felonies has its roots in the Common Law of England, where it was used to classify crimes like murder, rape, and burglary.  (Common law felonies included murder, rape, mayhem, robbery, sodomy, larceny, arson, manslaughter, and burglary). 

What is considered a misdemeanor or felony can vary by jurisdiction. Examples of misdemeanors include petty theft, prostitution, and public intoxication, while felonies can include arson, robbery, or murder. In some cases, crimes can be both misdemeanors and felonies, depending on the specific circumstances. For example, a battery resulting in a handprint on the victim’s face may be a misdemeanor, while a kick that breaks the victim’s ribs may be a felony.

In addition, minor breaches of the law that don’t result in incarceration are classified as violations and are punished with fines. The exact classification of different crimes will be explored in more detail later. These distinctions are also reflected in popular culture, where those convicted of felonies are often called felons, and those convicted of misdemeanors are sometimes called misdemeanants.

🔍 Reflect

How does the classification of crimes into felonies, misdemeanors, and violations impact the criminal justice process and the penalties imposed on offenders?

Measuring Crime

Crime statistics are an essential tool for understanding the nature and scope of criminal activity. These statistics can help law enforcement agencies identify crime trends and patterns, which in turn can inform the allocation of resources and the development of effective crime prevention strategies. Crime statistics are also used to evaluate the effectiveness of justice programs and policies.  If the rate of a particular crime is falling, then what the system is doing will seem to be working.  If the rate of a particular crime rises, it will indicate that the criminal justice system is failing.

The primary source of crime statistics in the United States is the FBI’s Uniform Crime Reports (UCR). The UCR is a crime data collection submitted by thousands of local and state law enforcement agencies nationwide. This data includes information on crimes reported to the police, such as homicide, robbery, assault, and theft. The FBI compiles this data into an annual report and other special reports that focus on specific issues.

While the UCR is a widely used and essential source of crime statistics, it does have limitations. For example, not all crimes are reported to the police, and the UCR only captures crimes brought to law enforcement’s attention. Additionally, the UCR does not provide information on the characteristics of the perpetrators or victims of crimes, which can be important for understanding the social and demographic factors that contribute to criminal activity.

Since its inception in the 1930s, many people have been critical of the UCR system for various reasons. Among these reasons is that the UCR includes only crimes reported to the police and only counts the most serious crime committed in a series of crimes. It does not differentiate between completed crimes and attempts and does not include many types of crimes, such as white-collar and federal crimes. 

Another critical complaint (especially among scholars) was that the UCR did not obtain potentially important information about the victim, the offender, the location of the crime, and so forth. Social scientists could not use the UCR data to explain and predict crime without this information. These complaints eventually led to the development of a much more informative crime reporting system known as the National Incident-Based Reporting System (NIBRS).

The NIBRS is an incident-based reporting system in which agencies collect data on each crime occurrence (Federal Bureau of Investigation, n.d.). NIBRS data come from local, state, and federal automated records systems. The NIBRS collects data on every single incident and arrest within 22 offense categories made up of 46 specific crimes called Group A offenses. For each of the offenses coming to the attention of law enforcement, specified types of facts about each crime are reported. In addition to the Group A offenses, there are 11 Group B offense categories for which only arrest data are reported (Federal Bureau of Investigation, n.d.).

According to the FBI, participating in NIBRS can benefit agencies in several ways. The benefits of participating in the NIBRS are:

  •  The NIBRS can furnish information on nearly every major criminal justice issue facing law enforcement today, including terrorism, white-collar crime, weapons offenses, missing children where criminality is involved, drug/narcotics offenses, drug involvement in all offenses, hate crimes, spousal abuse, abuse of the elderly, child abuse, domestic violence, juvenile crime/gangs, parental abduction, organized crime, pornography/child pornography, driving under the influence, and alcohol-related offenses.
  • Using the NIBRS, legislators, municipal planners / administrators, academicians, sociologists, and the public will have access to more comprehensive crime information than the summary reporting can provide.
  •  The NIBRS produces more detailed, accurate, and meaningful data than traditional summary reporting. Armed with such information, law enforcement can better make a case to acquire the resources needed to fight crime.
  • The NIBRS enables agencies to find similarities in crime-fighting problems so that agencies can work together to develop solutions or discover strategies for addressing the issues.
  • Full participation in the NIBRS provides statistics to enable a law enforcement agency to provide a full accounting of the status of public safety within the jurisdiction to the police commissioner, police chief, sheriff, or director.
  • The National Incident-Based Reporting System (NIBRS) is being implemented and adopted by more law enforcement agencies across the United States. According to the FBI, as of 2021, over 7,900 law enforcement agencies are submitting NIBRS data, a significant increase from the 5,271 agencies in 2004. This represents over 41% of the U.S. population and over 40% of the crime statistics collected by the UCR Program. Although there is still work to be done to achieve universal implementation, progress is being made faster due to technological advancements, increased funding, and the efforts of state and federal agencies to encourage adoption. As more agencies adopt NIBRS, there is hope that crime data will become more accurate and comprehensive, providing a more complete picture of crime in the United States.

A commonly cited problem with the UCR is that many crimes do not come to the attention of the police. This is not limited to minor offenses. For example, nearly half of all rapes are estimated to go unreported. These undocumented offenses are often referred to as the dark figure of crime. This is why the United States Bureau of Justice Statistics (BJS) developed the National Crime Victimization Survey (NCVS). The NCVS, which began in 1973, provides a detailed picture of crime incidents, victims, and trends.

According to the latest available statistics from the BJS (2020), the NCVS estimated that U.S. residents aged 12 or older experienced an estimated 3.5 million violent victimizations and 6.6 million property victimizations. The NCVS also reported that about half of all violent victimizations and about a third of property victimizations were reported to the police.

Two times a year, U.S. Census Bureau personnel interview household members in a nationally representative sample of approximately 42,000 households (about 75,000 people). About 150,000 interviews of persons aged 12 or older are conducted annually. Households stay in the sample for three years. New households are rotated into the sample on an ongoing basis.

The NCVS collects information on crimes suffered by individuals and households and whether victims reported those crimes to law enforcement. It estimates the proportion of each crime type reported to law enforcement and summarizes the reasons that victims give for reporting or not reporting.

The survey provides information about victims (age, sex, race, ethnicity, marital status, income, and educational level), offenders (sex, race, approximate age, and victim-offender relationship), and the crimes (time and place of occurrence, use of weapons, nature of injury, and economic consequences). Questions also cover the experiences of victims with the criminal justice system, self-protective measures used by victims, and possible substance abuse by offenders. Supplements are added periodically to the survey to obtain detailed information on topics like school crime. BJS publication of NCVS data includes Criminal Victimization in the United States, an annual report covering the broad range of detailed information collected by the NCVS.

🔍 Reflect

Why is it important to have multiple methods, like the UCR, NIBRS, and NCVS, for measuring crime, and what are the strengths and limitations of each approach?

Index Crimes

The Federal Bureau of Investigation (FBI) designates certain crimes as Part I or index offenses because it considers them both serious and frequently reported to the police. The Part I offenses are as follows:

Criminal homicide: Murder and nonnegligent manslaughter: the willful (nonnegligent) killing of one human being by another. Deaths caused by negligence, attempts to kill, assaults to kill, suicides, and accidental deaths are excluded.

Forcible rape: The carnal knowledge of a female forcibly and against her will. Rapes by force and attempts or assaults to rape, regardless of the victim’s age, are included. Statutory offenses (no force used-victim under age of consent) are excluded.

Robbery: The taking or attempting to take anything of value from the care, custody, or control of a person or persons by force or threat of force or violence and/or by putting the victim in fear.

Aggravated assault: An unlawful attack by one person upon another for the purpose of inflicting severe or aggravated bodily injury. This type of assault usually is accompanied by the use of a weapon or by means likely to produce death or great bodily harm. Simple assaults are excluded.

Burglary (breaking or entering): The unlawful entry of a structure to commit a felony or a theft. Attempted forcible entry is included.

Larceny-theft (except motor vehicle theft): The unlawful taking, carrying, leading, or riding away of property from the possession or constructive possession of another. Examples are thefts of bicycles, motor vehicle parts, and accessories, shoplifting, pocket-picking, or the stealing of any property or article that is not taken by force and violence or by fraud. Attempted larcenies are included. Embezzlement, confidence games, forgery, check fraud, etc., are excluded.

Motor vehicle theft: The theft or attempted theft of a motor vehicle. A motor vehicle is self-propelled and runs on land surface and not on rails. Motorboats, construction equipment, airplanes, and farming equipment are specifically excluded from this category.

Arson: Any willful or malicious burning or attempt to burn, with or without intent to defraud, a dwelling house, public building, motor vehicle or aircraft, personal property of another, etc.

🔍 Reflect

Why do you think the FBI designates certain crimes as Part I or index offenses, and how might this classification impact law enforcement priorities and public perceptions of crime?

Key Terms

Aggravated Assault, Arson, Burglary, Common Law Felonies, Criminal Homicide, Dark Figure of Crime, Felon, Forcible Rape, Index Offenses, Larceny-theft, Mala In Se, Mala Prohibita, Misdemeanant, Motor Vehicle Theft, National Crime Victimization Survey (NCVS), National Incident-Based Reporting System (NIBRS), Omission, Rate, Robbery, U.S. Census Bureau, Uniform Crime Reports (UCR), Victimless Crime, Violation


[Back | Contents | Next]

Last Modified:  05/16/2024
Cite This Page (APA)

McKee, A. J. (2024). Defining and measuring crime. In Criminal justice: An overview of the system (Section 1.3). Retrieved July 18, 2024, from

This work is licensed under an Open Educational Resource-Quality Master Source (OER-QMS) License.

Open Education Resource--Quality Master Source License

Print for Personal Use

You are welcome to print a copy of pages from this Open Educational Resource (OER) book for your personal use. Please note that mass distribution, commercial use, or the creation of altered versions of the content for distribution are strictly prohibited. This permission is intended to support your individual learning needs while maintaining the integrity of the material.

Print This Text Section Print This Text Section

2 thoughts on “Section 1.3: Defining and Measuring Crime

  1. I really enjoyed reading about this article because it informed me about different agencies and there roles they come with. This made me understand how law works. Before reading this article I had some questions about misdemeanors and felonies and there consequences,but this article gave me the information that helped me understand on how there’s different ways we define crimes and what can be the consequences depending on state or county.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.