Marrying a first cousin is illegal in Oregon because state law specifically bans such unions and treats them as void, not just discouraged. Oregon’s marriage code prohibits marriages between first cousins and any closer blood relatives, whether the relationship is through full‑blood, half‑blood, or adoption.
If a first cousin couple tries to get legally married in Oregon, the marriage is considered invalid from the start and cannot be recognized by the state, even if a ceremony is held.
Who is barred from marrying in Oregon
Oregon Revised Statutes list clear categories of people who cannot lawfully marry, and first cousins are included in that list along with parents, children, siblings, aunts, uncles, nieces, and nephews. The key statute, ORS 106.020, declares that marriages between “first cousins or any nearer of kin” are prohibited and void if solemnized in Oregon, meaning the state will not treat the union as a legal marriage at all.
This rule applies equally to biological and half‑siblings, and even to close relatives by adoption, except in one narrow situation: first cousins who are related only by adoption and not by blood can still marry without running afoul of this ban.
For more distant relatives, Oregon’s rules are less strict. Second cousins and more distant kin are allowed to marry, so someone who is a second cousin rather than a first cousin can obtain a valid marriage license in Oregon. The main legal line is drawn at first‑cousin closeness; anything beyond that falls outside the state’s incest‑based prohibition for marriage.
Incest laws and criminal consequences
Beyond the civil‑marriage ban, Oregon also has a criminal incest statute that can apply depending on the specific relationship involved. Under ORS 163.525, a person commits incest if they marry or engage in sexual intercourse with someone they know to be an ancestor, descendant, or brother or sister (whole or half‑blood).
Incest is classified as a Class C felony in Oregon, which can carry significant prison time and fines, so the law is not only about invalidating marriages but also about criminalizing certain intimate relationships.
For first cousins, the main legal consequence is usually that the marriage is void rather than automatically treated as a felony, but anything closer than first‑cousin—such as siblings or half‑siblings—can trigger both invalid‑marriage and criminal‑incest penalties. Courts and prosecutors look at whether the parties knew of the relationship, how closely related they are, and whether sexual activity took place in order to decide whether to pursue criminal charges.
Practical implications and what couples can do
If a couple are first cousins and want to have a legal marriage, they would need to get married in a state that allows first‑cousin unions and then rely on federal and interstate recognition rules, which can be complicated. Even if they marry elsewhere, Oregon may still refuse to recognize the marriage for certain state‑level purposes, such as divorce proceedings, child custody, and some benefits.
In short, Oregon law clearly says that you cannot legally marry your first cousin within the state, and any attempt to do so produces a void marriage rather than a valid one. Second cousins and more distant relatives, however, are allowed to marry, and special rules exist for first‑cousin‑by‑adoption couples who are not biologically related.
Anyone in a close‑family relationship considering marriage should consult an Oregon family‑law attorney to understand how the statutes apply to their specific situation.
SOURCES:
- https://oregonlawhelp.org/topics/family/getting-married-oregon
- https://getordained.org/state-marriage-laws/oregon
