Source: http://www.knifeden.com/knife-laws-in-oregon/
Timestamp: 2019-04-24 20:23:31+00:00

Document:
Other than a few basic guidelines concerning illegal concealed carry and a law regarding possession of knives and other weapons by felons, knife laws in Oregon are defined almost exclusively via case law rather than statutory law. This leaves certain matters unfortunately vague, such as the precise blade length at which an ordinary pocketknife (legal to concealed carry) becomes a dangerous weapon (illegal to concealed carry). A switchblade is eligible for concealed carry due to another case establishing it as a type of pocketknife. There are essentially no limits on knife ownership, however, except for those imposed on felons.
Any kind of knife can be openly carried in Oregon. Concealed carry is further complicated by a lack of statewide preemption and various local ordinances restricting this right even more closely than state law.
For people who are not convicted felons and who reside in Oregon, there are no limits to knife or bladed implement ownership or to the blades which can be carried in the home. KA-BAR knives, machetes, swords, sword-canes, throwing stars, gravity knives, ballistic knives, throwing knives, balisong knives, hunting, fishing, and skinning knives, Bowie knives, survival knives, single-edged and double-edged fixed blade knives of all sizes, disguised knives such as lipstick dirks or belt-buckle knives, and all other kinds of knife can be bought, sold, manufactured, owned, given or received by private individuals.
Section § 166.270 of the Oregon Revised Statutes of 2013 forbids a convicted felon to even own a switchblade knife, a dirk, a dagger, an automatic knife, or a stiletto. All of these are knives otherwise legal to own in Oregon, making the Oregon knife law stricter than most other states, where felons can own all legal knives even though they are typically forbidden to carry them outside their own premises.
Open carry of any legal knife is unrestricted except on school grounds, at schools, in courthouses, prisons, and certain posted government buildings.
The state of Oregon has never attempted to limit the length of knives or blades that can be owned or open carried. A pocketknife with a blade 4.75” long is proven by case law to be legal to carry, while one with a blade 6” long is not; the knife length limit for concealed carry lies somewhere in between.
According to the Oregon Revised Statutes of 2013, section § 166.240, it is a misdemeanor to carry dirks, daggers, ice picks, knives whose blades deploy via a spring or centrifugal force, or any “similar instruments” concealed. Extensive annotations attached to the section use case law to clarify the statute and ensure it is not unconstitutionally vague.
Two case law precedents, City of Portland v. Elston, 39 Or App 125, 591 P2d 406 and State v. Harris 40 Or App 317, 594 P2d 1318, both occurring in 1979, lead the state to declare that section § 166.240 means that it is illegal to carry any knife concealed except for a pocketknife.
Another 1979 opinion, State v. Strong, 41 Or App 665, 598 P2d 1254, established that a pocketknife with a folding 4.75” blade is legal to carry concealed. State v. Witherbee in 1986 further established that a 6” blade is illegal and no longer counts as a pocketknife. However, the case does not establish a firm limit and even directly admits that it is “vague” but that this vagueness is not a legal defense. Therefore, the boundary of blade length legality for a concealed carry pocketknife lies somewhere between 4.75” (legal) and 6” (illegal), with no official indication of the dividing line.
Muddying the waters even more, State v. Ramer, 671 P2d 723 in 1983 created a precedent whereby a switchblade is legal to concealed carry as a pocketknife because the Webster’s Third New International Dictionary defined a switchblade as a “pocket knife.” The defendant, Michael Lloyd Ramer, was still convicted for carrying a stabbing weapon, however, making the verdict basically incomprehensible.
Oregon supports robust knife ownership and knife open carry rights. The Beaver State’s concealed carry rights enable carrying a pocketknife with a blade up to 4.75” long legally, but provide no exact upper limit. Local ordinances supply additional complexity. Independence, OR allows pocketknives with blades 3.5” or shorter to be concealed, while Lebanon and Troutdale make a 3.5” blade illegal and state the blade must be under 3.5” to be carried out of sight. Research of local ordinances before carrying is prudent.

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