2017 ORS 254.365¹
Voting at primary election by major party members and nonaffiliated electors

(1) An elector is not qualified or permitted to vote at any primary election for any candidate of a major political party, and it is unlawful for the elector to offer to do so, unless:

(a) The elector is registered as being affiliated with one of the major political parties nominating or electing its candidates for public office at the primary election; or

(b) The elector is registered as not being affiliated with any political party and wishes to vote in the primary election of a major political party that has provided under subsection (3) of this section for a primary election that admits electors not affiliated with any political party.

(2) Except as provided in ORS 254.470 (Procedures for conducting election by mail) (3), any elector offering to vote at the primary election shall be given a ballot of the major political party with which the elector is registered as being affiliated. The elector may not be given a ballot of any other political party at that primary election. An elector not affiliated with any political party and offering to vote at the primary election shall be given the ballot of the major political party in whose primary election the elector wishes to vote if that party has provided under subsection (3) of this section for a primary election that admits electors not affiliated with any political party. An elector not affiliated with any political party who is given a ballot of the major political party associates with the party for the purpose of voting in that primary election.

(3)(a) Not later than the 90th day before the date of the primary election, a major political party may file with the Secretary of State a certified copy of the current party rule allowing an elector not affiliated with any political party to vote in the party’s primary election. The party may not repeal the rule as filed during the 90 days before the primary election. The rule shall continue to be effective after the date of the primary election until the party gives written notice to the Secretary of State that the rule has been repealed. Except as provided in paragraph (b) of this subsection, a party rule under this subsection may limit the candidates for whom an elector who is not affiliated with any political party may vote.

(b) The party rule shall allow any elector who is permitted to vote for the most numerous branch of the Legislative Assembly also to vote in federal legislative elections, consistent with section 2, Article I, and the Seventeenth Amendment to the United States Constitution.

(4) If the primary election ballot includes city, county or nonpartisan offices or measures, and it is given to an elector who is not eligible to vote for party candidates, the ballot shall be marked “non-affiliated.” [Formerly 249.366; 1987 c.719 §§1,20; 1995 c.712 §62; 1999 c.999 §51; 2007 c.154 §34]

See also annota­tions under ORS 249.366 in permanent edi­tion.

Atty. Gen. Opinions

Unconstitu­tionality of requiring po­lit­i­cal parties to allow nonmembers to vote in primary elec­tions, (1977) Vol 38, p 765; po­lit­i­cal party permitting voters who are not affiliated with such party to participate in primary elec­tion for choice of its candidates, (1981) Vol 41, p 466

1 Legislative Counsel Committee, CHAPTER 254—Conduct of Elections, https://­www.­oregonlegislature.­gov/­bills_laws/­ors/­ors254.­html (2017) (last ac­cessed Mar. 30, 2018).
 
2 Legislative Counsel Committee, Annotations to the Oregon Revised Stat­utes, Cumulative Supplement - 2017, Chapter 254, https://­www.­oregonlegislature.­gov/­bills_laws/­ors/­ano254.­html (2017) (last ac­cessed Mar. 30, 2018).
 
3 OregonLaws.org assembles these lists by analyzing references between Sections. Each listed item refers back to the current Section in its own text. The result reveals relationships in the code that may not have otherwise been apparent.