New York State prohibits carrying a knife with the intent to use the same unlawfully against another. In short, you should have a legal reason for carrying a knife. If that reason can be job related, even better.
There must be two elements proven: (1) possession of a dangerous knife (defined below from case law) and (2) intent to use unlawfully against another. Regarding intent to use, case law notes that:
Of course, that a knife is dangerous does not alone make out a charge of fourth-degree criminal possession of a weapon, since the statute makes criminal a dangerous knife only when possessed with intent to use it unlawfully against another. But “[t]he possession by any person of any dagger, dirk, stiletto, dangerous knife or any other weapon, instrument, appliance or substance designed, made or adapted for use primarily as a weapon, is presumptive evidence of intent to use the same unlawfully against another” (Penal Law § 265.15[4] ). Thus, by alleging facts of an evidentiary character which, if true, establish that defendant possessed a dangerous knife, the information sufficiently pleads, based on the statutory presumption, that he possessed a weapon with the requisite criminal intent.
Coming here from the UK I am not sure if this is applicable, but I underlined subsection 5 below which eliminates the intent to use unlawfully element for non US citizens.
Here is the NY Statute:
§ 265.01 Criminal possession of a weapon in the fourth degree
A person is guilty of criminal possession of a weapon in the fourth degree when:
(1) He or she possesses any firearm, electronic dart gun, electronic stun gun, gravity knife, switchblade knife, pilum ballistic knife, metal knuckle knife, cane sword, billy, blackjack, bludgeon, plastic knuckles, metal knuckles, chuka stick, sand bag, sandclub, wrist-brace type slingshot or slungshot, shirken or “Kung Fu star”; or
(2) He possesses any dagger, dangerous knife, dirk, razor, stiletto, imitation pistol, or any other dangerous or deadly instrument or weapon with intent to use the same unlawfully against another; or
(3) He or she knowingly has in his or her possession a rifle, shotgun or firearm in or upon a building or grounds, used for educational purposes, of any school, college or university, except the forestry lands, wherever located, owned and maintained by the State University of New York college of environmental science and forestry, or upon a school bus as defined in section one hundred forty-two of the vehicle and traffic law, without the written authorization of such educational institution; or
(4) He possesses a rifle or shotgun and has been convicted of a felony or serious offense; or
(5) He possesses any dangerous or deadly weapon and is not a citizen of the United States; or
(6) He is a person who has been certified not suitable to possess a rifle or shotgun, as defined in subdivision sixteen of section 265.00, and refuses to yield possession of such rifle or shotgun upon the demand of a police officer. Whenever a person is certified not suitable to possess a rifle or shotgun, a member of the police department to which such certification is made, or of the state police, shall forthwith seize any rifle or shotgun possessed by such person. A rifle or shotgun seized as herein provided shall not be destroyed, but shall be delivered to the headquarters of such police department, or state police, and there retained until the aforesaid certificate has been rescinded by the director or physician in charge, or other disposition of such rifle or shotgun has been ordered or authorized by a court of competent jurisdiction.
(7) He knowingly possesses a bullet containing an explosive substance designed to detonate upon impact.
(8) He possesses any armor piercing ammunition with intent to use the same unlawfully against another.
Criminal possession of a weapon in the fourth degree is a class A misdemeanor.
Notable exceptions:
Possession of a switchblade or gravity knife for use while hunting, trapping or fishing by a person carrying a valid license issued to him pursuant to section 11-0713 of the environmental conservation law.
A “dangerous knife” is “a knife which may be characterized as a weapon” ( Matter of Jamie D ). A “weapon,” in turn, is “an instrument of offensive or defensive combat” ( id.). Thus, although some knives may satisfy the test of dangerousness by virtue of their “inherent characteristics,” a knife not necessarily designed for combative use “may nonetheless be determined to fall within the statutory prescription when the circumstances of its possession including the behavior of its possessor demonstrate that the possessor himself considered it a weapon” ( id. at 591; see also Matter of Sean R ). Accordingly, a knife “designed and primarily intended for use as [a] utilitarian utensil [ ]” will be deemed dangerous within the meaning of the statute when either it has been converted by physical modification into a weapon or the circumstances of its possession “may permit a finding that on the occasion of its possession it was essentially a weapon rather than a utensil” ( Jamie D., 59 ). People v. Richards, 22 Misc.3d 798, 869 N.Y.S.2d 731
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