§ 10-133 Possession of knives or instruments. a. Legislative findings. It is hereby declared and found that the possession in public places, streets and parks of the city, of large knives is a menace to the public health, peace, safety and welfare of the people of the city; that the possession in public places, streets and parks of such knives has resulted in the commission of many homicides, robberies, maimings and assaults of and upon the people of the city; that this condition encourages and fosters the commission of crimes, and contributes to juvenile delinquency, youth crime and gangsterism; that unless the possession or carrying in public places, streets and parks of the city of such knives without a lawful purpose is prohibited, there is danger of an increase in crimes of violence and other conditions detrimental to public peace, safety and welfare. It is further declared and found that the wearing or carrying of knives in open view in public places while such knives are not being used for a lawful purpose is unnecessary and threatening to the public and should be prohibited.
b. It shall be unlawful for any person to carry on his or her person or have in such person’s possession, in any public place, street, or park any knife which has a blade length of four inches or more.
c. It shall be unlawful for any person in a public place, street or park, to wear outside of his or her clothing or carry in open view any knife with an exposed or unexposed blade unless such person is actually using such knife for a lawful purpose as set forth in subdivision d of this section.
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[Subsection d lists a number of exceptions, e.g., for law enforcement, military, EMTs on duty, etc. that typically would not apply to most visitors]
N.Y.C. Admin. Code (2005), excerpted from Knife Laws of the Fifty States: A Guide for the Law-Abiding Traveler, p. 114
