Substantive law includes laws that define crime. They tell us what elements the government needs to prove in order to establish that this crime has been committed. Substantive law also includes the definitions of inchoate crimes (incomplete crimes) of conspiracies, solicitations, and attempts. Substantive law also sets forth accomplice liability (when a person will be held responsible when they work in concert with others to complete a crime). Substantive law also identifies the defenses that a person may raise when they are charged with a crime. Finally, substantive law indicates the appropriate penalties and sentences for crimes. Today, the great majority of substantive law has been codified and is found in the state’s particular criminal code or in the federal code.

4.8.1 Elements of the Crime

The government will generally be responsible for proving that the defendant committed some criminal act, the actus reus element, and that defendant acted with criminal intent, the mens rea element. When prosecuting the crime, the state must prove that the defendant’s conduct met the specific actus reus requirement. The government must prove that the defendant’s behavior was either a voluntary act, a voluntary omission to act when there was a legal duty to do so, or that he or she possessed some item that should not have been possessed. To meet the mens rea element, the state must, at a minimum, prove that the defendant’s act was triggered by criminal intent.

4.8.2 Inchoate Offenses: Attempt, Conspiracy, and Solicitation

In order to prevent future harm, state and federal governments have enacted statutes that criminalize attempts, solicitations, and conspiracies to commit crimes. The common law also recognized these inchoate offenses or incomplete offenses. With each of the inchoate crimes, the state must prove that the defendant intended to commit some other crime, the highest level of criminal intent. For example, there is no crime of attempt, but there is a crime of attempted theft. State laws vary in the approaches of whether the defendant has taken enough steps to be charged with attempt, but all agree that mere preparation does not constitute an attempt. Conspiracies involve an agreement between at least two parties to commit some target crime. Some jurisdictions also require that there be an overt act in furtherance of the crime, which reaffirms there is a meeting of the minds between the co-conspirators. Solicitations involve a person asking another to commit a crime on his or her behalf, and they do not even require an agreement by the person requested to do so.

4.8.3 Accomplice Liability: Raiders and Abetters

People who commit crimes frequently do so with assistance. Substantive criminal law describes when a person can be found guilty for the acts of another. For example, the common law recognized four parties to a crime: principal in the first degree, principal in the second degree, accessory before the fact, and accessory after the fact. Many complicated legal rules developed to offset the harsh common law treatment of most crimes as capital offenses (death penalty eligible). The modern statutory trend has been to recognize both accomplices, people who render assistance before and during the crime, and accessories after the fact, people who help the offender escape responsibility after the crime has been committed. Accomplices, as treated as equally liable as the main perpetrator as “the hand of one, is the hand of them all.” Accessories, after the fact, are charged with hindering prosecution or obstructing justice after the crime are punished to a lesser extent than the main perpetrators.

4.8.4 Vicarious Liability

A few states have enacted vicarious liability statutes seeking to hold one person responsible for another’s actions, even when they did not provide any assistance and may not even know about the other’s behavior. These statutes generally violate our belief in individual responsibility that only people who do something wrong should be blamed for the crime. Vicarious liability imputes (transfers) both the criminal intent and the criminal act of one person to another. Courts generally invalidate these purported vicarious liability statutes but have at times upheld liability based upon an employer/employee relationship or a parent/child relationship.

4.8.5 Defenses

Assuming the government has proven all the elements of a crime, defendants may nevertheless raise defenses that may result in their acquittal. Defense is a general term that includes perfect and imperfect defenses, justifications and excuses, and procedural defenses.

4.8.5.1 Perfect and Imperfect Defenses

A perfect defense is one that completely exonerates the defendant. If the defendant is successful in raising this defense, meaning the jury believes him or her, the jury should find the defendant not guilty. An imperfect defense is one that reduces the defendant’s liability to that of a lesser crime. If the jury believes the defendant, it should find the defendant guilty of a lesser charge.

4.8.5.2 Negative Defenses and Affirmative Defenses

Sometimes, the government is unable to prove all the elements of the crime charged. When this happens, the defendant may raise a negative defense claim. For example, when charging a defendant with theft, the state must prove that the defendant intentionally took the property of another. If the jury finds that the defendant did not intend to take the property, or took property that was rightfully theirs, then the defendant is not guilty. Negative defenses, at their essence, are claims that there are “proof problems” with the state’s case.

An affirmative defense requires the defendant to put on evidence that will persuade the jury that he or she should either be completely exonerated or be convicted only of a lesser crime. The defendant can meet this requirement by calling witnesses to testify or by introducing physical evidence. When the defendant raises an affirmative defense, the burden of production or persuasion switches, at least in part and temporarily, to the defendant. The defendant’s burden is limited, however, to prove the elements of the defense he or she asserts.

4.8.6 Justifications

Sometimes, doing the right thing results in harm. Society recognizes the utility of doing some acts in certain circumstances that unfortunately result in harm. In those situations, the defendant can raise a justification defense. Justification defenses allow criminal acts to go unpunished because the resulting harm is outweighed by the benefit to society. For example, if a surgeon operates to remove a cancerous growth, the act is beneficial even though it results in pain and scarring. In raising a justification defense, the defendant admits he did a wrongful act but argues that the act was the right thing to do under the circumstances. Justification defenses include self-defense, defense of others, defense of property, defense of habitation, consent, and necessity, also called choice of evils. Justifications are affirmative defenses. The defendant must produce some evidence in support of these defenses. In most cases, the defendant must also convince the jury that it was more likely than not that their conduct was justified. For example, the defendant may claim that they acted in self-defense and, at trial, would need to call witnesses or introduce physical evidence that supports the claim of self-defense.

4.8.7 Excuses

Excuses are defenses to criminal behavior that focus on some characteristic of the defendant. With excuses, the defendant is essentially saying, “I did the crime, but I am not responsible because I was . . . insane (or too young, intoxicated, mistaken, or under duress).” Excuses include insanity, diminished capacity, automatism, age, involuntary intoxication, duress, mistake of fact, and a variety of non-traditional syndrome excuses. Like justifications, excuses are affirmative defenses in which the defendant bears the burden of putting on some evidence to convince the jury that they should not be held responsible.

4.8.8 Procedural Defenses

Procedural defenses are challenges to the state’s ability to bring the case against the defendant for some valid reason. Procedural defenses include:

• double jeopardy (the defendant claims that the government is repeatedly prosecuting them for the same crime),
• speedy trial (the defendant claims the government took too long to get their case to trial),
• entrapment (the government in some way enticed them into committing the crime),
• the statute of limitations (the government did not charge him or her within the required statutory period), and
• several types of immunity (they are immune from being prosecuted).

Although procedural defenses are considered procedural criminal law, many states include the availability of these defenses in their substantive criminal codes.