Self-defense (self-defence in many varieties of English) is a countermeasure that involves defending the health and well-being of oneself from harm. The use of the right of self-defense as a legal justification for the use of force in times of danger is available in many jurisdictions, but the interpretation varies widely.
Physical self-defense is the use of physical force to counter an immediate threat of violence. Such force can be either armed or unarmed. In either case, the chances of success depend on a large number of parameters, related to the severity of the threat on one hand, but also on the mental and physical preparedness of the defender.
Many styles of martial arts are practiced for self-defense or include self-defense techniques. Some styles train primarily for self-defense, while other martial or combat sports can be effectively applied for self-defense. Some martial arts train how to escape from a knife or gun situation, or how to break away from a punch, while others train how to attack. To provide more practical self-defense, many modern day martial arts schools now use a combination of martial arts styles and techniques, and will often customize self-defense training to suit the participants' lifestyles, occupations, age groups and gender, and physical and mental capabilities.
A wide variety of weapons can be used for self-defense. The most suitable depends on the threat presented, the victim or victims, and the experience of the defender. Legal restrictions also greatly influence self-defence options.
In many cases there are also legal restrictions. While in some jurisdictions firearms may be carried openly or concealed expressly for this purpose, there are also jurisdictions with tight restrictions on who can own firearms, and what types they can own. Knives, especially those categorized as switchblades may also be controlled, as may batons, pepper spray and personal stun guns and Tasers - although some may be legal to carry with a licence or for certain professions.
Non-injurious water-based self-defense indelible dye-marker sprays, or ID-marker or DNA-marker sprays linking a suspect to a crime scene, would in most places be legal to own and carry.
Everyday objects, such as flashlights, baseball bats, newspapers, keyrings with keys, kitchen utensils and other tools, and hair spray aerosol cans in combination with a lighter, can also be used as improvised weapons for self-defense. Tie-wraps double as an effective restraint. Weapons such as the Kubotan (pocket stick) have been built for ease of carry and to resemble everyday objects. Ballpoint pen knives, swordsticks, cane guns and modified umbrellas are similar categories of concealed self-defense weapons that serve a dual purpose.
Mental self-defense is the ability to get into the proper mindset for executing a physical self-defense technique. Many martial arts schools and self-defense classes focus primarily on the physical nature of self-defense and often neglect the mental aspect. If you are skilled in the physical aspects of a defensive technique, but lack the mental toughness and tenacity to execute it, you will not be able to perform - especially under duress. Controlled environments cannot easily mimic the stress and adrenaline dump which occurs during an attack. There is a very real need to be able to enter the proper "warrior mindset" if one is to have a realistic chance of surviving a potentially deadly encounter. This warrior mindset is the ability to focus purely on the successful outcome of a situation without becoming concerned with the consequences, even if they prove fatal in the dedicated pursuit of your desired outcome. The ability to go over, under, around or through any obstacle is the essence of this "never quit" mindset - similar to that of the Samurai of Japan. Self-preservation is a very powerful motivator and it is essential for ensuring that one has the mental toughness and proper mindset to emerge the victor in an encounter with one or more attackers/aggressors.
Being aware of and avoiding potentially dangerous situations is one useful technique of self-defense. Attackers will typically select victims they feel they have an advantage against, such as greater physical size, numerical superiority or sobriety versus intoxication. Additionally, any ambush situation inherently puts the defender at a large initiative disadvantage. These factors make fighting to defeat an attacker unlikely to succeed. When avoidance is impossible, one often has a better chance at fighting to escape, such methods have been referred to as 'break away' techniques. Understanding the 'mindset' of a potential attacker is essential if we are to avoid or escape a potentially life-threatening situation.
Verbal Self Defense, also known as Verbal Judo or Verbal Aikido, is defined as using one's words to prevent, de-escalate, or end an attempted assault. It is a way of using words as weapons or as a shield. This kind of 'conflict management' is the use of voice, tone, and body language to calm a potentially violent situation before violence actually ensues. This often involves techniques such as taking a time-out, and deflecting the conversation to individuals in the group who are less passionately involved, or simply entering into protected empathic position to understand the attacker better. Lowering an attackers defence and raising his ego is one way to de-escalate a potential violent situation.
Personal alarms are a way to practice passive self-defense. A personal alarm is a small, hand-held device that emits strong, loud, high-pitched sounds to deter attackers because the noise will sometimes draw the attention of passersby. Child alarms can function as locators or device alarms such as for triggering an alert when a swimming pool is in use to help prevent dangerous situations in addition to being a deterrent against would-be aggressors.
Self-defense techniques and recommended behavior under the threat of violence is systematically taught in self-defense classes. Commercial self-defense education is part of the martial arts industry in the wider sense, and many martial arts instructors also give self-defense classes. While all martial arts training can be argued to have some self-defense applications, self-defense courses are marketed explicitly as being oriented towards effectiveness and optimized towards situations as they occur in the real world. It should not be presumed however that sport based systems are inadequate, as the training methods employed regularly produce well conditioned fighters experienced in full contact fighting. There are a large number of systems taught commercially, many tailored to the needs of specific target audiences (e.g. defense against attempted rape for women, self-defense for children and teens). Notable systems taught commercially include:
The self-defense laws of modern legislation build on the Roman Law principle of dominium where any attack on the members of the family or the property it owned was a personal attack on the pater familias and also on biblical sources, namely Exodus. In Leviathan (1651), Hobbes argues that although some may be stronger or more intelligent than others in their natural state, none are so strong as to be beyond a fear of violent death, which justifies self-defense as the highest necessity. In his 1918 speech Politik als Beruf (Politics as a Vocation), Max Weber defined a state as an authority claiming the monopoly on the legitimate use of force within defined territorial boundaries. Modern libertarianism characterizes the majority of laws as intrusive to personal autonomy and, in particular, argues that the right of self-defense from coercion (including violence) is a fundamental human right. In this context, note that Article 12 Universal Declaration of Human Rights states:No one shall be subjected to arbitrary interference with his privacy, family, home or correspondence, nor to attacks upon his honour and reputation. Everyone has the right to the protection of the law against such interference or attacks.
Combined with the principle of the state's monopoly of legitimate force, this means that those authorized by the state to defend the law (in practice, the police) are charged with the use of necessary force to protect such rights. The right to self-defense is limited to situations where the immediate threat of violence cannot be prevented by those authorized to do so (in practice, because no police force is present at the moment of the threat). The right to self-defense granted by law to the private citizen is strictly limited. Use of force that goes beyond what is necessary to dispel the immediate threat of violence is known as excessive self-defense (also self-defense with excessive force). The civil law systems have a theory of "abuse of right" to explain denial of justification in such cases. Thus, in English law, the general common law principle is stated in Beckford v R (1988) 1 AC 130:"A defendant is entitled to use reasonable force to protect himself, others for whom he is responsible and his property. It must be reasonable."
Similar clauses are found in the legislation throughout the western world. They derive historically from article 6 of the French Penal Code of 1791, which ruled that "manslaughter is legitimate if it is indispensably dictated by the present necessity of legitimate defense of oneself or others". The modern French penal code further specifies that excessive self-defense is punishable due to "disproportion between the means of defense used and the gravity of the attack" defended against.
The evaluation of whether use of force was excessive in a given case can be a difficult task. The British Law Commission Report on Partial Defenses to Murder (2004) Part 4 (pp78/86) recommends a redefinition of provocation to cover situations where a person acts lethally out of fear. This reflects the present view of psychiatrists that most people act in violent situations with a combination of fear and anger in their minds, and to separate these two types of affect is not legally constructive. In practice, self-defense laws still do make this distinction. German criminal law (§ 33) distinguishes "asthenic affect" (fear) from "sthenic affect" (anger). Excessive self-defense out of asthenic affect is not punishable.
Outside of the western world, justifiable self-defense tends have very similar parameters, including limitations to reasonable or proportionate use of force based on the magnitude of the crime. But there may be exceptions that are hard to reconcile with human rights. For instance, the Intermediate People's Court of Foshan, People's Republic of China in a 2009 case ruled as justifiable self-defense, the killing of a robber who was trying to escape, because "the robbery was still in progress" at this time.