Washington Constitution Art. 2, § 14. Same, Federal or Other Office

No person, being a member of congress, or holding any civil or military office under the United States or any other power, shall be eligible to be a member of the legislature; and if any person after his election as a member of the legislature, shall be elected to congress or be appointed to any other office, civil or military, under the government of the United States, or any other power, his acceptance thereof shall vacate his seat, provided, that officers in the militia of the state who receive no annual salary, local officers and postmasters, whose compensation does not exceed three hundred dollars per annum, shall not be ineligible.