Pennsylvania

Pennsylvania – Pa. C.S.A. 18.908. Prohibited offensive
weapons. (a) Offense defined.–A person commits a
misdemeanor of the first degree if, except as authorized
by law,  he makes, repairs, sells, or otherwise deals in,
uses, or possesses any offensive weapon. (b) Exception.–
It is a defense under this section for the defendant to
prove by a preponderance of evidence that he possessed of
dealt with the weapon solely as a curio or in a dramatic
performance, or that he possessed it briefly in
consequence of having found it or taken it from an
aggressor, or under circumstances similarly negativing any
intent or likelihood that the would be used unlawfully.
(c) Definition.–As used in this section “offensive
weapon” means… any… dagger, knife, razor or cutting
instrument, the blade of which is exposed in an automatic
way by switch, push-button, spring mechanism, or
otherwise…
– also see 24 P.S. 13-1317.2. re: students bringing weapons
on to school property.]

Pennsylvania case law:
Where opening knife required lock to be released, and
once lock was released blade could be exposed by flip of
wrist, knife did not have blade which could be “exposed in
an automatic way”… by “otherwise” legislature referred
to knives that were opened by some sort of mechanism which
is not a “switch,” “push-button,” or “spring” mechanism
but still a mechanism… (1979)

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Full text:

Title 18 § 908. Prohibited offensive weapons.
(a) Offense defined.–A person commits a misdemeanor of the first degree if, except as authorized by law, he makes repairs, sells, or otherwise deals in, uses, or possesses any offensive weapon.

(b) Exceptions.–

It is a defense under this section for the defendant to prove by a preponderance of evidence that he possessed or dealt with the weapon solely as a curio or in a dramatic performance, or that, with the exception of a bomb, grenade or incendiary device, he complied with the National Firearms Act (26 U.S.C. 5801 et seq.), or that he possessed it briefly in consequence of having found it or taken it from an aggressor, or under circumstances similarly negativing any intent or likelihood that the weapon would be used unlawfully.
This section does not apply to police forensic firearms experts or police forensic firearms laboratories. Also exempt from this section are forensic firearms experts or forensic firearms laboratories operating in the ordinary course of business and engaged in lawful operation who notify in writing, on an annual basis, the chief or head of any police force or police department of a city, and, elsewhere, the sheriff of a county in which they are located, of the possession, type and use of offensive weapons.
This section shall not apply to any person who makes, repairs, sells or otherwise deals in, uses or possesses any firearm for purposes not prohibited by the laws of this Commonwealth.

(c) Definition.–As used in this section, the following words and phrases shall have the meanings given to them in this subsection:

“Firearm.”
Any weapon which is designed to or may readily be converted to expel any projectile by the action of an explosive or the frame or receiver of any such weapon.
“Offensive weapons.”
Any bomb, grenade, machine gun, sawed-off shotgun with a barrel less than 18 inches, firearm specially made or specially adapted for concealment or silent discharge, any blackjack, sandbag, metal knuckles, dagger, knife, razor or cutting instrument, the blade of which is exposed in an automatic way by switch, push-button, spring mechanism, or otherwise, or other implement for the infliction of serious bodily injury which serves no common lawful purpose.

(d) Exemptions.–The use and possession of blackjacks by the following persons in the course of their duties are exempt from this section:

Police officers, as defined by and who meet the requirements of the act of June 18, 1974 (P.L.359, No.120), referred to as the Municipal Police Education and Training Law.
Police officers of first class cities who have successfully completed training which is substantially equivalent to the program under the Municipal Police Education and Training Law.
Pennsylvania State Police officers.
Sheriffs and deputy sheriffs of the various counties who have satisfactorily met the requirements of the Municipal Police Education and Training Law.
Police officers employed by the Commonwealth who have satisfactorily met the requirements of the Municipal Police Education and Training Law.
Deputy sheriffs with adequate training as determined by the Pennsylvania Commission on Crime and Delinquency.
Liquor Control Board agents who have satisfactorily met the requirements of the Municipal Police Education and Training Law.

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Title 18 § 912. Possession of weapon on school property.
(a) Definition.–Notwithstanding the definition of “weapon” in section 907 (relating to possessing instruments of crime), “weapon” for purposes of this section shall include but not be limited to any knife, cutting instrument, cutting tool, nun-chuck stick, firearm, shotgun, rifle and any other tool, instrument or implement capable of inflicting serious bodily injury.

(b) Offense defined.–A person commits a misdemeanor of the first degree if he possesses a weapon in the buildings of, on the grounds of, or in any conveyance providing transportation to or from any elementary or secondary publicly-funded educational institution, any elementary or secondary private school licensed by the Department of Education or any elementary or secondary parochial school.

(c) Defense.–It shall be a defense that the weapon is possessed and used in conjunction with a lawful supervised school activity or course or is possessed for other lawful purpose.

Pennsylvania Knife Rights Bill

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