The Martial Artists' Guide to Civil and Criminal Liability in Physical Altercations

Martial arts refers to combat training techniques applied in a systematic way. These training techniques are designed to confront and defeat imminent threats of bodily harm or death. Widely-known forms of martial arts include Aikido, Brazilian Jiu-Jitsu (BJJ), Judo, Karate, Krav Maga, Kung Fu, Mixed Martial Arts (MMA), Muay Thai, Taekwondo, and Tang Soo Do. A person who practices martial arts is known as a martial artist.[1]

Are You a Deadly Weapon?

While it's entertaining to watch Steven Segal play a martial artist who must register his hands as deadly weapons, there is no state law that requires this. There is however, precedent for courts to consider parts of the human body to be deadly weapons under certain circumstances.[2] You also do not need to inform an adversary of your martial arts credentials.

It's only in the U.S. territory of Guam that "any person who is an expert in the art of karate or judo, or any similar physical art in which the hands and feet are used as deadly weapons, is required to register with the Department of Revenue and Taxation."[3][4]

Self-Defense: Your Actions, Your Liability

To limit your civil and criminal liability, consider the consequences of using your martial arts skills outside the confines of your dojo.[5]

In self-defense, the purpose of martial arts is to protect oneself or another person from an imminent threat of bodily injury or death. The martial artist must be fully aware of the consequences of intentionally or unintentionally misusing their skills. A misuse of skills can result in criminal prosecution, a civil judgment, or both.[6]

Specifically, you must understand the legal difference between a controlled, necessary and proportionate force to repel an attack, and an excessive and disproportionate force. Excessive and disproportionate use of force can make you criminally or civilly liable for any personal injuries or property damages you cause.[7][8]

Unfortunately, the specific circumstances when an attack is non-existent, minimal, or not imminent are not specified in law. Each case of self-defense is reviewed individually and subjectively, though in some cases the threat is so real and imminent as not to be questioned.[9]

To reduce the likelihood of misusing your martial arts skills, first make every attempt to diffuse and neutralize a threat without violence. If you are unable to diffuse or neutralize an aggressor without force, or if there isn't enough time to try to diffuse or neutralize the threat, then you can safely use your martial arts skills to repel the threat. Make sure that you use only the amount of force necessary to repel the assault.

Criminal Liability

You are criminally liable when you wrongfully and willfully use your skills to repel an attack that is non-existent, minimal, or not imminent. A person who is held criminally liable for excessive and disproportionate use of force may be arrested and charged with a crime, such as a misdemeanor or felony assault charge.

Misdemeanor assault can result in a probationary sentence, a fine of several hundred dollars, or incarceration in a county jail for one or two years.[10] Felony assault charges can result in a fine of several thousand dollars and incarceration in a state or federal penitentiary for a number of years, or in the event of death, it may result in lifetime imprisonment.[11]

Police Involvement and Criminal Prosecution

The police may become involved in a dispute for any of the following reasons:

  • Police are dispatched to a fight in progress at the request of a member of the public, such as the assault victim or a bystander.
  • The assault victim files a complaint with the police.
  • The police come upon a fight in progress while on patrol.[12]

Once involved, the police may proceed with any of the following actions:

  • Make an arrest at the scene of the fight.
  • Complete an incident report, submit it to their supervisors for review, and make an arrest if deemed appropriate by their supervisors. The police may take into account information regarding the parties' martial arts or boxing skills, military training, or similar experience.
  • Turn over the investigation to the prosecutor in the office of the district attorney, county attorney, or attorney general for further investigation.

A prosecutor who is responsible for an assault case may proceed with any of the following actions:

  • Dismiss the case due to insufficient evidence to prosecute.
  • Issue an arrest warrant for the alleged assailant.
  • Submit the case to the grand jury for consideration because the severity of the case is deemed to qualify as a felony.

Criminal Liability: Case Study

Given your understanding of criminal liability in the excessive and disproportionate use of force, consider the following scenario and the appropriate course of action...

You are a Taekwondo practitioner. You and your friend Sue are driving out of a restaurant parking lot when your car collides with Tom's car. No one is physically hurt and the damage to the vehicles is minimal. While surveying the damage, Tom screams at you and Sue, and he threatens to sue you and physically assault you.

Consider the following reactions and consequences:

  1. You remain calm and offer to exchange insurance information. You acted appropriately by neutralizing the situation.

  2. You use your Taekwondo skills to seriously injure Tom because he has threatened to physically hurt you. You overreacted to a benign threat and are now subject to arrest and criminal prosecution.

  3. You realize that Tom is drunk, and allay his attempt to physically attack you by knocking him to the ground with one strike. You acted appropriately by using proportionate force to repel the attack.

  4. You see that Tom is about to strike Sue, and allay his attempt to physically attack Sue by knocking him to the ground with one strike and rendering him momentarily unconscious. You acted appropriately by defending Sue with proportionate force to repel the attack.

  5. You see that Tom has procured a lead pipe from his car and is about to strike you and Sue. You allay his attempt to physically attack you both by striking Tom repeatedly, causing him to bleed and fall to the ground. While Tom has been rendered unconscious for several minutes, you report the incident to emergency services. You acted appropriately by using proportionate force to repel Tom's obvious intent to inflict serious bodily injury.

  6. You see that Tom has procured a long knife and is about to lunge at you. After knocking Tom to the ground, you and Sue run to your vehicle to escape Tom. Again, Tom lunges at you with the knife. This time, you strike Tom repeatedly and consequently kill him. You acted appropriately by defending yourself and Sue from an imminent threat of serious bodily injury or death. You used proportionate force for as long as was necessary to retreat and stop Tom from inflicting serious bodily injury.

Civil Liability

You are civilly liable when you act in a negligent, willful, or wanton manner that results in property damage or another person's injuries. You may not be criminally liable for your disproportionate or excessive use of force, but the person who suffered injuries or property damages may file a lawsuit against you in a civil court for damages.

Damages can include medical and therapy bills, out-of-pocket expenses (for medications, bandages, etc.), lost wages, and for pain and suffering. Damages can also include the costs of repairing or replacing damaged property.[14]

Civil Liability: Case Study

(This example demonstrates consequences of using excessive and disproportionate force...)

You are a mixed martial arts (MMA) practitioner. One day, upon leaving your gym, you are confronted by two drunk and aggressive people who demand that you give them your wallet. They threaten to physically attack you. They do not appear to have weapons, but you believe they will seriously harm you and you fear for your safety.

You confront the two people using your MMA skills and knock both people to the ground. One of them flees, but the other remains on the ground, and after several minutes, he begins to rise to his feet. You attack him again causing serious bodily harm, including a broken arm and nose, cuts to his eyes, and a concussion.

Following your attack, you call emergency services. The paramedics take the man to the hospital, and the police inform you that you acted in self-defense of a crime and will not be prosecuted. Later on, the injured man is charged with attempted robbery.

After the injured man's criminal trial, he files a $100,000 personal injury lawsuit against you. The lawsuit alleges that you used unnecessary, disproportionate, and excessive force to inflict serious bodily injury, and that your actions amount to willful and grossly negligent conduct.

The case goes to civil court. During the trial, the jury hears all of the evidence, including testimony from you, both men who attempted to rob you, the police officers, and the paramedics. You testify that you are an MMA expert with five years of cage fighting experience.

At the end of the trial, the judge instructs the jury that they can take into account your MMA skills in determining whether you used intentional, willful, negligent and disproportionate force.

The judge also instructs the jury that in order for them to find in favor of the plaintiff (the injured man), there must be a preponderance of evidence that you willfully or negligently inflicted serious bodily harm. This means that by the end of the trial the jury can only rule in favor of the party who has the most evidence to support their case.

Note that "preponderance of evidence" is different from "beyond a reasonable doubt." Beyond a reasonable doubt is the burden of proof a prosecutor has in a criminal trial, not a civil trial.[15]

The jury ruled in favor of the injured man, stating you were 60% negligent in causing his injuries. You used excessive force to cause serious bodily harm when it was not necessary. You could have easily left the scene after you initially subdued the attackers. Instead, you remained at the scene for several minutes after the threat had been neutralized, and willfully caused serious bodily injury.

(This example depends heavily on state law.)

Stand Your Ground Doctrine: No Duty to Retreat

Currently, thirty-two states have adopted the Stand Your Ground doctrine. This doctrine upholds your right to use reasonable force, including deadly force, to protect your own life or the life of another person without having to retreat from the place you occupy at the time of the real or perceived threat.[16]

The following states uphold the Stand Your Ground doctrine: Alabama, Alaska, Arizona, Florida, Georgia, Indiana, Kansas, Kentucky, Louisiana, Michigan, Mississippi, Montana, North Carolina, North Dakota, New Hampshire, Nevada, Oklahoma, Oregon, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, Utah, West Virginia, Wisconsin, and Wyoming.[17]

Castle Doctrine: Make My Day

Currently, twenty-five states have adopted the Castle doctrine, also known as the "Make My Day" doctrine.[18][19] The Castle doctrine upholds that a lawful occupant who is within their residence is justified in using reasonable and proportionate force, including deadly force, against an intruder in order to prevent the intruder from forcibly entering the residence.

According to the Castle doctrine, the occupant must legitimately and reasonably believe that the intruder intends to commit a felony in the residence and that deadly force is necessary to repel the intruder. In addition, a lawful occupant of a residence does not have a duty to retreat from an intruder.

The following states uphold the Castle doctrine: Alaska, California, Connecticut, Delaware, Hawaii, Idaho, Illinois, Kansas, Maine, Massachusetts, Michigan, Minnesota, Missouri, New Jersey, New York, North Carolina, North Dakota, Ohio, Oregon, Rhode Island, South Carolina, South Dakota, West Virginia, Wisconsin, and Wyoming.[20]

State Codes of Law: Self-Defense Legislation


  1. Martial Info The complete List of Martial Arts Styles
  2. The Human Body - A Deadly Weapon
  3. Official Port Island of Guam
  4. Guam Code Annotated
  6. Self Defense Law and the Martial Artist Peer Hobart Esq.
  7. Ronald B. Standler Copyright 1998 Differences Between Civil and Criminal Law in the USA
  8. Pattern Jury Instructions for Excessive Force in Violation of the Fourth, Eighth, and Fourteenth Amendment
  9. Lawrence A. Kane
  10. Criminal, What is a Misdemeanor
  11. Criminal Defense What is a Class A Felony
  12. News Mixed Martial Arts Police Arrests
  13. American Taekwondo Association
  14. Cornell Law School "Damages"
  15. Cornell University Law School
  16. Stand Your Ground The Wire News from the Atlantic
  17. Washington Post
  18. Castle Doctrine - OLR Research Report
  19. The Phrase Finder Clint Eastwood "Sudden Impact"
  20. The Castle Doctrine and Stand Your Ground Law

Additional Sources

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