Self-Defense Law: Overview

Self-defense is using force or violence to protect oneself, or a third person, from imminent harm. In other words, the victim reasonably believes they are in immediate danger of imminent death, bodily injury, or serious bodily harm. This definition may seem simple enough, but it raises many questions when someone uses it in real life.

It is a widely accepted principle that a person has the legal right to self-defense and the defense of others. This is also true when that defense would normally amount to a crime. Self-defense is an affirmative defense. Each state allows a defendant to claim self-defense as a legal defense when accused of a violent crime, such as a murder charge. Federal criminal law allows this as well.

The specific laws on self-defense cases vary from state to state. Some states have stand-your-ground laws, while others do not. This article addresses the broad concepts of self-defense law in the U.S. You should check the laws of your state to understand the requirements for a claim of self-defense.

What Is Self-Defense?

Courts struggle with determining an appropriate level of force or violence when a person defends themselves. In reviews of what is such appropriate levels of violence, courts often consider the following:

  • What if the victim of a violent crime provoked the attack?
  • Did the perpetrator threaten the use of deadly force or non-deadly force?
  • Was the victim obligated to retreat from the violence or threat of imminent force?
  • Did the victim have a reasonable belief or reasonable fear that the use of force against them was imminent?
  • Did the victim use reasonable force in response to the attack?
  • What protection exists for victims who feel, on reasonable grounds, that a threat exists when it does not?

Self-defense law is more complicated than it first appears. To handle the many circumstances under which self-defense occurs, states have created rules to determine when self-defense is allowed. These rules also decide how much force a victim can use to protect themselves.

Is the Threat Imminent?

Generally, self-defense only justifies using force in response to an imminent threat. For a threat to be imminent, it must be certain to occur. Such a threat can be made with words as long as it puts the intended victim in a reasonable and immediate fear of physical harm or serious bodily injury. Without such a threat, offensive words do not justify the use of force in self-defense.

Consider the following scenario for an example of such a situation. A jealous ex-lover confronts his former girlfriend and shouts, "I'm going to kill you!" He brandishes a knife and steps forward. In this case, the victim would be within her rights to defend herself because a reasonable person would fear physical harm. So, if she had pepper spray in her purse, she's justified in using it to fend off her angry ex-lover. Had he approached her and said, "We need to talk," she would not be legally justified in using the pepper spray in self-defense.

The use of force in self-defense loses justification once the threat has ended. For example, if an aggressor assaults a victim but then stops doing so and indicates that there is no longer any threat of violence, the threat of danger has ended. Any use of force by the victim against the perpetrator at that point is retaliatory and not self-defense.

Consider the following scenario. Two players in a basketball game argue over a foul call until one punches the other in the face. After delivering the punch, the player quits the game and leaves the gym. A few hours later, the two players coincidentally encounter each other in the grocery store. At this point, the original confrontation is over. Absent a new attack or imminent threat of harm, the punched player would not be legally justified in punching the player who hit him earlier. Under this circumstance, the use of force is retaliatory and not self-defense.

Was the Fear of Harm Reasonable?

Self-defense is legally justified even if the perceived aggressor did not mean the perceived victim any harm. What matters in these situations is whether a "reasonable person" in the same situation would have perceived an immediate threat of physical harm.

Under the legal concept of the "reasonable person," legal systems decide whether a person's feelings and experience of imminent danger justify the use of force as a response to a threat.

Imagine two strangers walking past each other in a city park. A bee is buzzing around the head of one of the two people. The other person sees this. Being friendly, the other person reaches quickly to try to swat the bee away from the bee's soon-to-be victim. The person with the bee by their head, only seeing a stranger's hand move quickly toward their face, might understandably slap the other person's hand away violently.

In other circumstances, the slap would amount to a textbook assault. But a court could easily find that the sudden movement of a stranger's hand toward a person's face would cause a reasonable person to conclude that they were in danger of immediate physical harm. This would likely render the use of force a justifiable exercise of the right to self-defense. It would not matter that the perceived attacker meant no harm and was, in fact, actually trying to help.

Imperfect Self-Defense

Sometimes, a person may genuinely fear imminent physical harm that is not objectively reasonable. If that person uses force to defend themselves from the perceived threat, the legal situation is "imperfect self-defense."

Imperfect self-defense does not excuse a person from the crime but can lessen the charges and penalties involved. But not every state recognizes imperfect self-defense as a reason to lessen a sentence.

For example, a student is studying at a coffee shop when a classmate arrives and walks toward the student. The classmate balls up his fist in anticipation of a friendly "fist-bump" greeting. The student genuinely fears that their classmate is preparing to punch them, even though this fear is unreasonable. In reaction to the perceived threat, the student flings his coffee cup at the classmate's face and scrambles away. While the student's claim of self-defense would not excuse any criminal charge for assault, it could reduce the severity of the charges. The student's self-defense claim is imperfect because of the unreasonable nature of how he perceived a threat.

Some states also consider instances where the person claiming self-defense provoked the attack as imperfect self-defense. For example, if a person creates a violent conflict, then unintentionally kills the other party while defending themselves, a claim of self-defense might reduce the charges or punishment. But the defense would not excuse the killing entirely.

Proportional Response

Self-defense law requires the response to match the threat level in question. In other words, a person can only use as much force as required to remove the threat. If the threat involves deadly force, the person defending themselves can use deadly force to counteract the threat. If the threat involves only minor force and the person claiming self-defense uses force that could cause grievous bodily harm or death, their claim of self-defense will fail.

Duty to Retreat

The original laws about self-defense required people claiming self-defense first to attempt to avoid violence before using force. This is also known as a "duty to retreat." While most states have removed this rule for instances involving non-deadly force, many states still require the person to attempt to escape the situation before applying deadly force. It's important to know the laws of your local jurisdiction to decide whether this duty is required.

Stand Your Ground

In contrast to the duty to retreat, many states have enacted so-called "stand your ground" laws. These laws remove the duty to retreat and allow for a claim of self-defense even if the person making the claim did nothing to flee from the threat of violence.

Today, this is the more common rule when situations involve nonlethal force. But states differ on whether the "stand your ground" principle applies to lethal force situations.

This article delineates which states have "stand your ground" laws and which use a different legal standard.

Castle Doctrine

Even in states that require a person to retreat from the threat of imminent harm before defending themselves, a person can often use deadly force against someone who unlawfully enters their home.

This rule, also known as "the castle doctrine," allows people to defend their homes against intruders through the use of lethal force.

Additional material on the castle doctrine is available on FindLaw. But when in doubt, it is always a good idea to consult a local attorney for legal advice.

Need Help With a Claim of Self-Defense?

Self-defense claims are fairly common. But the situations in which a person can defend themselves and how much force they can use are complicated. Everything is much simpler with the advice of a competent criminal defense lawyer. Find an experienced criminal defense attorney near you.

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