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AKTI Approved Knife Definitions

The American Knife and Tool Institute (AKTI) is a 501(c)6 nonprofit organization representing all aspects of the knife industry. As a part of its mission to educate and inform members of the knife community as well as the public, legislative and law enforcement entities about knives and knife laws, AKTI offers these definitions for knife designs or knife styles which are the subject of federal and /or state prohibitions.

AKTI suggests that law-abiding citizens should be able to carry knives, cutting tools, and for that matter edged weapons, without the fear of arbitrary, inconsistent and ineffective restrictions as to blade shape, style, length or other such characteristics.

AKTI further suggests that to the extent there are existing laws which prohibit the possession or carrying of certain types of knives, these laws must be construed narrowly and with deference to the United States Constitutional requirement of due process, as well as the right reserved to the citizens by the United States Constitution and the Constitutions of various states to keep and bear arms.

AKTI encourages law enforcement and the administration of criminal justice to be guided by these definitions. It must be noted, however, that these are recommendations, and AKTI cannot require any particular officer or court to observe them. Accordingly, AKTI cannot be responsible for any adverse consequences deriving from the misapplication or failure to apply these recommended definitions. See Expanded Introduction.

Also see:
Understanding Bias Toward Closure and Knife Mechanisms | Protocol for Measuring Blade Length


Ballistic Knife

A device by which a blade becomes separated from the handle and is propelled or becomes a missile, utilizing energy stored by some mechanism within the device. A ballistic knife does not include a cross bow, spear gun, or archery bow. Further, the term ballistic knife does not include an implement described or labeled as a “throwing knife” unless the blade of such throwing knife becomes separated from the handle during the intended and normal use of the device.

Comments on Ballistic Knives

Among those states which currently prohibit “ballistic knives” are Colorado, Florida, Georgia and Virginia.

Examples of a ballistic knife, which can be practically and routinely used as a knife in the conventional sense are unknown.

The distinguishing feature of a ballistic knife is that the blade can be launched or propelled as a projectile or missile separate from the handle. It is not inconceivable, however, that prohibitions as to ballistic knives might inappropriately be applied to a knife designed to be thrown. Accordingly, the definition includes the essential requirement of separation from the handle and the use of stored, as opposed to kinetic, energy. It is the position of AKTI that a ballistic knife should be regulated in the same manner as an archery bow, cross-bow, speargun, etc.

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Bias Toward Closure

The tendency to remain in the closed or folded position, imposed by a spring or mechanical load, unless acted upon by manual force.

For more see Understanding Bias Toward Closure and Knife Mechanisms.

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Bowie Knife

It is the position of AKTI that the term “Bowie Knife” is too vague and cannot be satisfactorily defined with sufficient precision. Accordingly, any law which provides an offense has been committed by one who possesses or carries a “Bowie Knife” is constitutionally defective.

Comments on Bowie Knives

“Bowie” knives are prohibited in such diverse states as Texas, Rhode Island, Illinois and Idaho There is, however, no definitive criteria as to what exactly constitutes a Bowie knife.

In September of 1827, a small group of individuals gathered on a sand bar along the river at Natchez, Mississippi for the purpose of fighting a duel. The members of this group included James Bowie, who was actually a “second” rather than one of the two principals to the duel. At some point, the orderly conventions of the duel were abandoned, and a melee developed, during which Bowie sustained three separate gunshot wounds, several edged-weapon wounds, and other trauma. Using a knife of some type, Bowie inflicted fatal wounds on two opponents.

There is no known definitive description or drawing of the knife that Bowie used in the 1827 Natchez sand bar fight. The whereabouts or disposition of the knife is similarly unknown.

Bowie’s success in that encounter caused him to achieve considerable celebrity, and the term “Bowie Knife” quickly entered the lexicon. Bowie’s status as a defender at the siege of the Alamo in 1836 no doubt cemented his place in American history. Everyone wanted a knife like that of Bowie, although few knew exactly what it looked like.

In the late 1820s and early 1830s, schools of knife fighting were established in and around New Orleans, Louisiana to teach the technique of fighting with the “Arkansas Toothpick” and/or “Bowie Knife.”(8) Concurrently, states in the lower Mississippi drainage acted to outlaw such knives. Typical of these was the Tennessee Law at Chapter 137 of the Acts of 1837-38, which provided as follows:

“Any person who carries under his cloths, or concealed about his person, a Bowie Knife, Arkansas Toothpick, or other weapon of like form, shape, or size, is guilty of a misdemeanor, . . .” Section 6630 of Shannon’s Code (Tennessee).

In the intervening 170 or so years since the Natchez Sandbar duel, the label “Bowie Knife” has been applied to a wide variety of styles. No agreement exists among historians as to exactly what constitutes a Bowie Knife. Given this uncertainty and a lack of agreement among people who have exhaustively studied and researched the topic, AKTI suggests that “Bowie Knife,” and for that matter “Arkansas Toothpick,” are terms which are simply too generalized and vague, and about which there would be too much potential for inconsistent application as to be enforceable under the United States Constitution.

If historians who have studied and researched the topic are incapable of agreeing on a definition of a Bowie Knife, then ordinary persons are not given sufficient guidance so that they may know exactly what is or is not prohibited.

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A knife having a generally straight fixed blade with dual effective cutting edges.

Comments on Daggers

A substantial numberof American jurisdictions prohibit the possession or carrying of daggers. Among those states are Hawaii, Massachusetts, Minnesota, Missouri, New Mexico and Iowa. However, there is no rational explanation as to why governments should prohibit daggers. Moreover, typically there is no guidance as to whether any given object is or is not a dagger. The California statutory definition is illustrative.

“As used in this section, a ‘dirk’ or ‘dagger’ means a knife or other instrument with or without a hand guard that is capable of ready use as a stabbing weapon that may inflict great bodily injury or death. A non-locking folding knife, a folding knife that is not prohibited by Section 653K, or a pocketknife is capable of ready use as a stabbing weapon that may inflict great bodily injury or death only if the blade of the knife is exposed and locked into position.” West’s Annotated California Penal Code, Section 12020( c)(24).

The California law provides that any person who “carries concealed upon his or her person any dirk or dagger” is subject to punishment by imprisonment for a period not exceeding one year. Section 12020(a)(4).

There is obviously a problem where a fundamental right reserved to the people under the Constitution is infringed by such an arbitrary and indefinite state law. We have the right to keep and bear arms. If the state must, for some compelling reason, restrict this right, then it must do so in the least restrictive manner and with specificity. The California definition of dagger, which is essentially an instrument capable of ready use as a stabbing weapon, is very non-specific, and for that matter, overboard.

The answer to the question of whether an item is or is not a dagger should not be determined on the basis of the identity of the person possessing the object nor, for that matter, the whim of a law enforcement officer. It should not turn on whether the person is wearing a biker vest or a vested suit. Moreover, a citizen should not need to seek expert advice from a military historian, or one who has studied the history and development of weapons. The law should be written with clarity.

AKTI notes that Section 5.07 of the Model Penal Code, captioned “Prohibited Offensive Weapons,” provides:

. . . “Offensive Weapon” means any bomb, machine gun, sawed-off shotgun, firearm specially made or specially adapted for concealment or silent discharge, a blackjack, sandbag, metal knuckles,dagger, or other implement for the infliction of serious bodily injury that serves no common lawful purpose (Model Penal Code Section 5.07 – emphasis supplied).

The authors of the Model Penal Code neither define dagger nor offer any explanation as to why it would be suitable only for offensive uses and have no other common, lawful purpose. AKTIsuggests that a knife coming within the suggested definition of a dagger can be a useful tool for innumerable lawful and especially defensive purposes. Given that we have a right to keep and bear arms, we should have a right to keep and bear effective arms. It makes no sense to cede the possession and bearing of effective edged weapons to those willing to live and act outside the law.

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It is the position of AKTI that the label “dirk” is too vague and cannot be satisfactorily defined with sufficient precision. Accordingly, any law which provides an offense has been committed by one who possesses or carries a dirk or dirk knife is constitutionally defective.

Comments on Dirks

Various states, including California (see comments for Dagger), Connecticut, Maine, Ohio, Georgia, New Mexico, Minnesota and Idaho prohibit dirks.

A modicum of research will reveal that what is now understood to be the “classic” or historically correct example of a “dirk” developed in mid-17th century Scotland. (9) This type of knife generally had one cutting edge with perhaps an opposing “swedge” (10) near the tip. The English government passed “Disarming Acts” in 1716 and 1725 in response to Scottish uprisings. These Acts focused on, among other things, Scottish swords and dirks. After another Scottish uprising in 1745-1746, the government outlawed kilts, clan tartans and other indicia of Scottish culture. It may be that there is a historical “anti-dirk” bias in Anglo-American law.

In the first half of the 19th century, a type of short sword, labeled the “navel dirk,” began to appear.(11) The naval dirk seems to have been more ceremonial than practical and was issued to or carried by mid-shipmen or young officers in training. This short sword was abandoned as the 19th century came to a close. In any event, the naval dirk bears almost no resemblance to the Scottish dirk which developed 200 years earlier. It is mentioned here to show that labels are often adopted or applied to different types of knives.

In any event, a type of knife that generally has one cutting edge, and perhaps an opposing swedge near the tip, could be almost anything. Absent the use of traditional Scottish handle materials or decorative touches, essentially any knife could come within the definition of dirk. This prohibition affords far too much leeway for inconsistent law enforcement and/or the inconsistent administration of justice.

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Effective Cutting Edge

An edge capable of performing ordinary, routine cutting tasks associated with activities such as food preparation or food service, or other common uses, including but not limited to farming, animal husbandry, gardening, building trades, hunting, fishing or any trade or crafts.

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Gravity Knife

A folding or moveable blade knife in which the blade is held in the closed position by a latch mechanism released by a button on the handle or other mechanical triggering device. A gravity knife does not include a knife that can be opened with one hand utilizing manual pressure applied to the blade, or to a thumb stud, declivity or spur of the blade; nor does gravity knife include a knife with a blade that can be opened by means of inertia or other such force produced by hand, wrist, arm or other bodily movement provided the knife has a detent, spring, structure or other such mechanism that provides a bias or spring-load toward the closed position.

Comments on Gravity Knives

So-called gravity knives are prohibited in such diverse states as Alaska, Connecticut, Colorado, Maine, North Dakota and New York.

Prohibitions pertaining to gravity knives are directly related to prohibitions regarding switchblades. For instance, the 1958 Federal Switchblade Act defines “switchblade” knife as any knife having a blade which opens automatically-

1. By hand pressure applied to a button or other device in the handle of the knife, or

2. By operation of inertia, gravity, or both. (12)

The term “gravity knife” occurs in a number of places within the legislative record concerning the 1958 Federal Switchblade Act. In those instances, there are specific references to the World War II German paratrooper or Fallschirmjager knife. (13)

There was perhaps a time in the post-World War II period extending into the mid-1950s, when souvenir German military paratrooper’s knives, brought back to this country, were routinely carried. These knives are rare and have long since become highly sought after by collectors.

While the gravity knife prohibitions were enacted to address an alternative to the switchblade, the gravity knife statutes are routinely applied to knives which cannot be opened by gravity and were never intended to be the subject of those 1950 era laws.

The Fallschirmjager knife was designed with a blade which extended from the handle in a telescoping fashion. In normal use, the Fallschirmjager knife was held in a vertical alignment with the front of the handle and the tip of the knife enclosed within that handle in the down position. Depressing a small lever or switch on the handle released the blade, and gravity pulled it into the down position where it mechanically latched. As an alternative to gravity, the user could generate inertial force by a flourishing movement of the arm, along with a coordinated release of the lever, which caused the blade to open and lock. This more flamboyant kinetic method was preferred by the teens of the late 1950’s (see below discussion as to Switchblades) and explains why many of the laws dating from the mid-to-late 1950’s, which proscribed switchblade knives, also apply to so-called “inertia knives” or “gravity knives.” One of the goals was to include the Fallschirmjager knife.

It should be noted that this paratrooper’s knife was not designed as a weapon, but rather as a tool to be used by an unfortunate paratrooper who became entangled in a tree during a descent. The blade could be exposed with only one hand (even the non-dominant hand) and could be used to cut the shroud lines, the harness, or perhaps small branches.

Eickhorn-Solingen Ltd., a successor to one of the World War II Fallschirmjager manufacturers, still produces a “rescue knife” using the same gravity opening design. It appears to be intended for the firefighter/first responder market.

Another form of so-called gravity knife emerged in the 1950’s as states began to prohibit switchblades.

Many of the switchblades popular with teenagers in the 1950’s were imported from Italy, and in particular, the Italian knifemaking center of Maniago. When prohibitions against spring-activated switchblade knives were put into effect, the Italian manufacturers sought to preserve their market by simply removing the spring, which drove the blade open when triggered by a push button on the handle. Outwardly, these knives resembled switchblades, complete with the button on the handle.

These knives did not have the spring action, but these knives also did not have a bias toward closure. American teens quickly perfected the kinetic opening method initiated by pushing the button followed by deft arm or wrist movement. The dramatic effect of the quick opening, as portrayed on the silver screen, was the objective. For the 1950’s era teen, the switchblade was neither a tool nor a weapon. Rather, it was a talisman, the display of which bestowed what might now be referred to as “street credibility.”

While the gravity knife prohibitions were enacted to address an alternative to the switchblade, the gravity knife statutes are routinely applied to knives which cannot be opened by gravity and were never intended to be the subject of those 1950 era laws.

In 2009, the Federal Switchblade Act was revised* so the gravity or inertia provisions would not be misapplied. The effect of the 2009 change is that the prohibitions of the Federal Switchblade Act do not apply to:

A knife that contains a spring, detent or other mechanism designed to create a bias toward closure of the blade and that requires exertion applied to the blade by hand, wrist or arm to overcome thebias toward closure to assist in opening the knife. (14)

Several other states, notably Texas and Kansas, have enacted similar changes. AKTI has an ongoing effort to achieve such legislative relief in other jurisdictions.

*Due to efforts of the AKTI and other organizations, incorporating AKTI’s Bias Toward Closure language, successfully first used in California in 2001

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Inertia Knife

See discussion and Comments relative to Gravity Knife.

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A knife with a blade that is exposed in an automatic way and moved from the closed position to the open position exclusively by the release of a compressed spring. A switchblade knife does not include a knife that opens with one hand, utilizing thumb pressure applied to the blade, or to a thumb stud, declivity, or spur of the blade, nor does switchblade include a knife with a blade that can be opened by means of inertia or other such force produced by hand, wrist, arm or other bodily movement, provided that the knife has a detent, spring, structure or other such mechanism that provides a bias toward closure which must be overcome in opening the blade.

(Also described as switch knife, flick knife, spring knife or automatic knife.)

Comments on Switchblades

Several states do not prohibit switchblades. Among them are Alabama, Arizona, and Oregon. Approximately one quarter of the states resisted the impulsive rush of the 1950 decade to outlaw switchblades. Several states, South Dakota and New Hampshire, have repealed switchblade prohibitions. Interestingly, an examination of Uniform Crime Report data does not suggest a relationship between crime levels including knife or cutting instrument crime and switchblade prohibitions.

Blackboard Jungle, a movie set in an urban high school, was released in March of 1955. The movie generated an extraordinary level of excitement among American youth.

Glenn Ford was cast in the role of an ethical, well-intentioned teacher named Richard Dadier, where he was opposed by the switchblade-wielding gang leader, Artie West, played by Vic Morrow. West derisively referred to Dadier as “Dadio,” a name which quickly entered the teen lexicon as a term of disrespect for teachers or adult authority figures. (15)

In October of 1955, Rebel Without a Cause, featuring James Dean in the role of a disaffected teenager, was released. This movie included a knife confrontation scene, which came to be a common feature in youth movies of that era. Teenagers adopted not only the language, but the clothing and props of the movie figures, which included switchblades.

The 1950’s era switchblades were nothing more than props for the teenagers and young adults of that era acting in their role as the disaffected generation. Many of the imported switchblade knives had blades of inferior steel which had not been tempered. This was of no consequence. The knives were never intended to actually cut anything after the dramatic opening.

The response was similar to that of the English government in reaction to the Scottish uprisings of the early 1700s – Disarming Acts (see Comments on Dirk). Many states moved quickly to outlaw switchblades with the Federal government enacting legislation in 1958, banning the production of switchblades for interstate commerce or sending switchblades through the mail.

Quality switchblade knives had been manufactured and widely sold since the early 20th century. Until these knives were stigmatized by movies such as Blackboard Jungle, they were commonly used by farmers and blue-collar workers throughout the first half of the 20th century who wanted a convenient way to open a pocketknife for some everyday task. Beginning in the mid-to-late 1950s, the switchblade took the place of the black handlebar mustache as a mark of the theatrical villain. In retrospect, the switchblade laws of the 1950s were an expediency of questionable constitutionality hurriedly passed to address a problem greatly magnified, if not created, by the movie industry.

The 1958 Federal Switchblade Act and the switchblade prohibitions enacted by various states during the 1950’s were a response to a teenager/young adult uprising, which was unsettling, but which did not involve knife crime. The real target of those laws was a specific demographic group, the members of which are now septuagenarians. The unnecessary and ill-conceived switchblade “disarming acts,” including the Federal Switchblade Act, should be repealed.

Switchblades are also sometimes referred to as “Automatics.” It is the position of AKTI that a “Switchblade” or “Automatic” is a knife in which the blade is open or exposed solely by means of stored mechanical energy released by a switch or the triggering mechanism, typically a button located on the handle of the knife. Accordingly, a knife in which there is some spring or mechanical assist would be excluded from this definition, provided that there is some bias or a spring load to the closed position and which must be overcome by thumb, finger or other manual movement applied to the blade.

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It is the position of AKTI that the label “stiletto” is too vague and cannot be satisfactorily defined with sufficient precision. Accordingly, any law which provides an offense is committed by one who possesses or carries a stiletto is constitutionally defective.

Comments on Stilettos

Stilettos are prohibited in, among other states, Connecticut, Iowa, Missouri, North Dakota and New Mexico.

See Comments on Dagger.

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Also see:
Understanding Bias Toward Closure and Knife Mechanisms | Protocol for Measuring Blade Length

Version 2012, Adopted 2005