defense | Definition

Doc's CJ Glossary by Adam J. McKee
Course: Criminal Law

In criminal justice, defense refers to the arguments and strategies used by an accused person to challenge the prosecution’s case.

When we talk about defense in the context of criminal justice, we’re referring to a broad concept that encompasses both a legal strategy and a critical role in the adversarial process of court proceedings. The term might call to mind a variety of images, from a lawyer delivering an impassioned speech in court to a defendant presenting evidence to refute the charges against them. However, understanding the nuances of what defense means in the criminal justice system can help us better appreciate its crucial role in ensuring a fair trial.

The Defense as a Legal Strategy

In the realm of criminal law, a defense is the set of arguments and evidence that an accused person (the defendant) uses to challenge the case brought against them by the prosecution. The aim of the defense is to raise doubts about the prosecution’s case in order to avoid a guilty verdict.

There are many types of defenses that a defendant might use, depending on the specifics of their case. For instance, they might argue that they didn’t commit the crime (factual), that they were somewhere else when the crime was committed (an alibi), or that they committed the act but were justified in doing so due to self-defense or duress (justification). Alternatively, they might argue that they committed the crime but were not responsible for their actions due to insanity or intoxication (excuse).

The Role of the Defense Attorney

A key figure in the defense is the defense attorney, who represents the defendant in court. The defense attorney’s role is to advocate for the defendant and to ensure that their rights are protected throughout the legal process. This includes advising the defendant, representing them in court, cross-examining prosecution witnesses, presenting evidence and arguments in favor of the defendant, and negotiating with the prosecution, such as in plea bargaining.

Defense attorneys have an ethical obligation to zealously represent their clients, even if they believe or know that the client is guilty. This is because the criminal justice system is based on the principle that every person is innocent until proven guilty, and every person has the right to a fair trial and to legal representation.

The Adversarial Process

The criminal justice system in many countries, including the United States, operates as an adversarial process. This means that two opposing sides – the prosecution and the defense – present their case before a neutral party, such as a judge or jury, who then decides the outcome.

In this context, the defense is not just a legal strategy but a party to the proceedings. The defense and the prosecution both have the opportunity to present their case, examine and cross-examine witnesses, and challenge the other side’s evidence and arguments. This adversarial process is intended to ensure a fair trial by enabling the defense to challenge the prosecution’s case and to present their own version of events.


The role of the defense in the criminal justice system cannot be overstated. The defense plays a vital part in maintaining the balance of the adversarial process and ensuring that the rights of the accused are upheld. Without a robust defense, there is a risk of miscarriages of justice, such as wrongful convictions.

Moreover, this contributes to the broader societal function of the criminal justice system. By challenging the prosecution’s case and advocating for the defendant, the defense helps to ensure that the state’s power to punish individuals is exercised responsibly and fairly.


In conclusion, defense in the criminal justice context is a multifaceted concept. It refers to the arguments and strategies used by a defendant to counter the prosecution’s case, and it also represents the key party in the adversarial process that advocates for the accused person. The defense’s role is instrumental in maintaining the balance in court proceedings, ensuring the rights of the defendant, and fostering a fair criminal justice system. The lawyer does not merely argue for the innocence of an individual; it ensures that the state’s power to prosecute and punish is exercised responsibly, fairly, and with respect to the rights of all individuals. Whether challenging the accuracy of evidence or arguing for the legitimacy of the defendant’s actions, the defense serves as a vital pillar in upholding justice.

[ Glossary ]

Last Modified: 05/15/2023


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.