By Dr. Gary L. Deel  |  07/14/2023

criminal law


Along with civil law, one of the subjects that all students learn about in law school is criminal law. Civil and criminal law differ greatly; some students prefer the field of civil law while others gravitate toward criminal law.  

Whether or not they become civil lawyers or criminal lawyers in their legal careers, understanding the concepts of criminal and civil law is extremely important. In this article, the focus is on criminal law.  


What is Criminal Law? 

Criminal law is the body of law that defines conduct perceived as threatening to, harmful to, or otherwise endangering the property, health, safety, and welfare of people.  

Within the realm of criminal law, there are many different types of crimes, each with their own set of punishments.  

Some common types of crimes include murder, assault, battery, theft, arson, drug offenses, fraud, rape, and sexual abuse. It’s also worth noting that while most crimes are offenses against other people or society in general, offenses against oneself are considered a criminal act as well. So suicide and attempted suicide are both criminal offenses. 


Where Does Criminal Law Come From? 

Most criminal laws are established by statute, which is to say that the laws are enacted by a legislature. In the United States, the federal government and each state have their own criminal codes, which define specific crimes and the different degrees of each crime.

The specific penalties for each degree of crime vary from jurisdiction to jurisdiction. Federal criminal law stands alone from each individual state's criminal law. 


Criminal Law Definition: Levels of Crime 

Generally, criminal law is defined by statutes with crimes classified based on the severity of crimes. Within the legal system, the most serious infringements of criminal law are felonies, followed by misdemeanors, and then infractions. 

Felonies are the most serious crimes. They are punishable by imprisonment in state prison, or in some cases, by death. Examples include murder, robbery, rape, arson, and drug trafficking. 

Misdemeanors are less serious than felonies. They are punishable by imprisonment in county jail, or by a fine. Examples include certain minor offenses such as theft, vandalism, certain property crimes, and disorderly conduct. 

Infractions or citations are even less serious crimes. They are punishable by a fine, but not by imprisonment. Examples include minor traffic violations, jaywalking, littering, public disorder and, other less serious offenses. 

Within each crime, there are also often degrees that taxonomize severity. The degree of a crime is determined by a number of factors, including the severity of the harm caused (including personal injury), the intent of the offender, and the offender's criminal history. 

For example, first-degree murder is the most serious level as it implies intent and premeditation. However, second-degree murder does not require a showing of premeditation and may be established by simply showing malice or reckless disregard for the lives of the victims. 


Punishment and Rehabilitation 

Criminal law also includes the punishment and rehabilitation of people who violate such laws. I have written previously about the differences between retributive and rehabilitative in criminal law system and justice philosophies

Criminal law varies according to jurisdiction, and differs from civil law, where emphasis is more on dispute resolution and victim compensation rather than on punishment or rehabilitation. Criminal procedure is a formalized official activity that requires proving the commission of a crime and meting out punitive or rehabilitative treatment for the offender. 

The Purpose of Criminal Law 

The purpose of criminal law is to protect society from harm from criminal behavior. Criminal law does this by deterring people from committing crimes, by punishing those who do commit crimes, and by rehabilitating those who have been convicted of crimes. 

Who Decides on Criminal Charges? 

In civil law, claims are brought by individuals or entities against one another, depending on the specifics of the lawsuits. In criminal law, charges for serious offenses are always brought by the state. And so the decision of whether or not to bring charges in a criminal case is made by a prosecutor. 

A prosecutor is an attorney who is responsible for representing the government in criminal cases. Prosecuting attorneys are typically elected officials, and they have the discretion to decide whether or not to charge someone with a crime. Many prosecutors in state and municipal offices carry the title of district attorney. 

The decision of whether or not to bring charges is a serious one. Prosecutors have a great deal of discretion in this area, and they must weigh a number of factors before making a decision. These factors include the strength of the evidence, the severity of the crime, the defendant's criminal history, and the public interest, including the wishes of the victims, if any. 

However, as I have written about previously, it is important to note that victims do not have the final say over whether or not to pursue charges against an offender. Again, that decision ultimately rests with the prosecutor. So if you’ve ever seen a movie or TV show where the victim is asked whether they want to press charges, just remember that their answer (either way) counts for little more than an opinion in these situations. 

The Criminal Process 

If a prosecutor does decide to bring charges, they will file a charging document with the court. The charging document will allege that the defendant has committed a crime, and it will specify the charges that the defendant is facing. 

Once the charging document is filed, the defendant will be arraigned. At the arraignment, the defendant will be informed of the charges that they are facing, and they will enter a plea of guilty, not guilty, or no contest. 

If the defendant pleads not guilty, the case will proceed to trial. At trial, the prosecutor will present evidence to the jury in an attempt to prove the defendant's guilt. The defendant will have the opportunity to present evidence in their own defense. 


What is the Evidentiary Standard in Criminal Law? 

The evidentiary standard in criminal law is proof beyond a reasonable doubt. This means that the prosecution must prove that the defendant is guilty of the crime beyond any reasonable doubt.

The jury must be convinced that the defendant is guilty, and that there is no other possible explanation for the evidence.  

This differs from the evidentiary standard in civil cases, which is merely proof by a preponderance of the evidence – meaning that a party must simply show that their claims or allegations are slightly more likely than not to be factually accurate in order to prevail. 

The standard of proof in criminal law is a very high standard. It is designed to protect the rights of the accused. The standard of proof is also designed to ensure that innocent people are not convicted of crimes. 

Philosophically, our society considers the notion of an innocent person being punished to be a greater injustice than the notion of a guilty person not being held to account. And so our criminal laws and criminal standards of proof are skewed accordingly in favor of innocence.

This is why all criminally accused persons are said to be “innocent until proven guilty” and not the other way around.


Who Has the Burden of Proof in Criminal Cases? 

In civil cases, the burden of proof is generally shared by plaintiffs and defendants – with plaintiffs having to present evidence of liability and defendants having to present evidence of blamelessness. 

But in criminal cases, the burden of proof is on the prosecution. The prosecuting attorney must prove the defendant's guilt beyond a reasonable doubt. The defense, on the other hand, does not have to prove anything. The defense can simply raise doubts about the criminal prosecution's case. 

Juries in Criminal Cases 

Juries in criminal cases will generally consist of 6-12 people. If a jury is not convinced that the defendant is guilty beyond a reasonable doubt, then the defendant must be acquitted. The defendant cannot be convicted if the jury has any reasonable doubt about the defendant's guilt. A jury can be requested in a civil case, too.

Jury Unanimity as a Requirement in Criminal Law 

In the federal court system and in virtually all state courts, jury verdicts in criminal cases must be unanimous. A hung jury, where even one juror is not convinced of guilt, would result in a mistrial and likely a retrial. This is why the voir dire process is so important in trial proceedings. 


Voir Dire 

"Voir dire," a French term meaning "to see, to speak the truth," is the jury selection process in a court case. In criminal trials, the judge and attorneys for both sides conduct voir dire with the aim to assemble an impartial jury capable of fairly considering trial evidence. 

Voir dire involves the judge and lawyers questioning potential jurors to assess their suitability for jury service. Questions span a range of topics, from knowledge of the case, to personal biases, and to their ability to uphold the law. Examples of voir dire queries might include: 

  • Have you been a crime victim? 
  • Are you acquainted with anyone involved in this case or alleged crime? 
  • Has media coverage shaped any of your opinions about this case? 
  • Can you adhere to the law, putting aside personal biases? 
  • Are you capable of deciding the case based on evidence, not personal beliefs? 

The judge and attorneys will also ask questions that are specific to the case at hand. For example, if the case involves a sexual assault, the judge and attorneys may ask potential jurors about their views on sexual assault. 

After voir dire, the judge will dismiss any potential jurors who are not qualified to serve on the jury. The remaining potential jurors will then be randomly selected to serve on the jury. 

Voir dire can be a long and challenging process. However, it is an important part of the criminal justice system. It helps to ensure that a fair and impartial jury is selected, which is essential for a just verdict. 


The Criminal Trial and Jury Sequestration 

During the trial itself, jurors usually come to court each day, listen to evidence and testimony, and then go home to their normal lives in between hearings. However, for some high-profile or sensitive cases, a judge may order jury sequestration. 

Jury sequestration is the process of isolating the jury from the public and media during a trial. This is done to prevent jurors from being exposed to outside information that could bias their decision. 

Sequestration is rare. Again, it is usually only ordered in high-profile cases where there is a risk of juror bias. In some cases, the judge may order sequestration only for certain jurors, such as those who have been exposed to media coverage of the case. 

When jurors are sequestered, they are typically housed in a hotel or other secure location. They are not allowed to watch television, read newspapers, or use the internet. They are also not allowed to talk to anyone about the case, except for their fellow jurors and the judge. 

Sequestration can be a difficult experience for jurors. They may feel isolated and bored. They may also feel pressure to reach a verdict quickly, in order to be released from sequestration. 

After the trial, the jury will deliberate and decide whether or not the defendant is found guilty. If the jury finds the defendant guilty, the defendant will be sentenced by the judge. 

Sentencing and Punishment 

The punishment for committing a crime can vary depending on the severity of the crime, the defendant's criminal history, (including any previous jail time) and other factors. Some common punishments for crimes include fines, probation, incarceration, and in the most serious cases, death. 


Skills Needed to Be a Competent Criminal Attorney 

Criminal law is a complex and ever-changing field. Criminal attorneys work on both sides of criminal prosecutions – pursuing charges and defending the accused. There are a number of skills that are essential for a successful criminal attorney, including: 

  • Legal Knowledge: Criminal attorneys need to have a deep understanding of criminal law, including the criminal code, the rules of evidence, and the procedures of the court system. 
  • Communication Skills: Criminal attorneys need to be able to communicate effectively with their clients, the prosecution, the judge, and the jury. They need to be able to explain complex legal concepts in a clear, concise, and persuasive way. 
  • Analytical Skills: Criminal attorneys need to be able to analyze the facts of a case and develop a legal strategy as it relates to criminal law. They need to be able to identify strengths and weaknesses in arguments on both sides in order to proceed effectively. 
  • Research Skills: Criminal attorneys need to be able to research the law and find relevant case law. They need to be able to keep up with changes in the law and to apply the law to the facts of their client's case. 
  • Writing Skills: Criminal attorneys need to be able to write clear and concise legal documents, such as motions, briefs, and trial transcripts - all based on criminal law. 
  • Interpersonal Skills: Criminal attorneys need to be able to build rapport with their clients, the prosecution, the judge, and the jury. They need to be able to communicate effectively with people from all walks of life. 
  • Resilience: Criminal attorneys often deal with difficult and stressful cases. They need to be able to handle stress and to remain calm under pressure. 

Students interested in a career path related to criminal law should consider getting a law degree from an accredited law school. 

After law school, they will need to pass the bar exam in the state where they want to practice law. Once they have passed the bar exam, they will be able to start their career as a criminal attorney. 

American Public University offers degrees in Legal Studies and in Criminal Justice.

About the Author
Dr. Gary Deel is an associate professor with the Dr. Wallace E. Boston School of Business at American Public University. He currently holds 13 degrees in areas such as space studies, hospitality and tourism management, psychology, higher education administration, and criminal justice, including a J.D. in Law and a Ph.D. in hospitality/business management. He is currently working on another degree and teaches human resources and employment law classes for American Public University, the University of Central Florida, Colorado State University, and others.

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