DC's legal definition of a statutory resident isn't quite the same as it is in most other locations:
“Resident” means an individual domiciled in the District at any time during the taxable year, and every other individual who maintains a place of abode within the District for an aggregate of 183 days or more during the taxable year..."
https://code.dccouncil.gov/us/dc/council/code/sections/47-1801.04
Note that the law does not say that the individual has to actually reside in DC for 183 days or more. I don't know if DC tax authorities would consider owning an apartment there for a full year as "maintaining a place of abode." You might have to ask the DC tax authorities about that.
If you are a statutory resident of DC, then your situation would be is one of dual residency: you'd be a domiciliary resident of OR and a statutory resident of DC.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
