(1) Existing statutory procedures set forth in RCW 36.04.400 and in RCW 36.05.010-36.05.080 do afford a legally sufficient means of establishing the location of disputed county boundary lines; however, this is not to say that these procedures possess optimum practical utility in view of the nature and extent of potential county boundary disputes. (2) The legislature may constitutionally create a county boundary line commission (in the general form provided for by House Bill No. 157) for the purposes set forth in your second question, as paraphrased. (3) The legislature may amend existing statutes describing the boundaries of county boundaries for the sole purpose of removing ambiguities and clarifying uncertainties, without violating the prohibition in Article II, § 28 (18). (4) The legislature may vest a boundary line commission with the power to hear and decide county boundary disputes and, by order, to conclusively locate and establish disputed county boundary lines on a prospective basis ‑ subject to compliance with pertinent criteria regarding the delegation of "quasi-judicial" power. (5) The legislature could, as a part of such legislation, preclude review in the courts by any of the counties involved or any citizen residing in the area affected, as to the prospective application of the true county boundary lines established by the boundary commission's order; however, no such administrative order could have the effect of determining private property rights required prior to the final adjudication of the true county boundaries.
AGO 1966 NO. 96 > Jul 21 1966
COUNTIES ‑- BOUNDARIES ‑- LOCATION OF DISPUTED, UNCERTAIN OR AMBIGUOUS LINES ‑- POWER OF LEGISLATURE ‑- CREATION OF BOUNDARY LINE COMMISSION