Definitions

The Public Service Commission's interpretation of the statute requires no "deference" per se. However practical the Commission's construction of the statute may appear, the statute as a whole, or in particular, certainly has not been subjected to any meaningful long and continued contemporaneous interpretation. Thus, the Commission's interpretation of the statute has simply not stood unchallenged for a considerable length of time and, obviously, has not been relied on by any party having an interest in the interpretation of the law. Thus, consistent with our standard of review, we shall focus our discussion and analysis on whether the Commission's interpretation of the statute was correct as a matter of law. Mont. Power Co. v. Mont PSC, 2001 MT 102, ¶ 27, 305 Mont. 260, 26 P.3d 91.

In reviewing conclusions of law under the Montana Administrative Procedures Act, we determine whether the agency's interpretation of the law is correct. The conservation district argues that its decisions are entitled to deference. However, while long-standing statutory interpretations by agencies are entitled to "respectful consideration," and we have acknowledged the value of the conservation district's expertise, no discretion is involved when a tribunal arrives at a conclusion of law—the tribunal either correctly or incorrectly applies the law. Bitterroot River Protective Ass'n v. Bietterroot Conservation Dist., 2008 MT 377, ¶ 18, 346 Mont. 507, 198 P.3d 219.

This Court is not bound to an agency's definition of a statutory term. Mont. Dep't of Revenue v. Priceline.com, Inc., 2015 MT 241, ¶ 14, 380 Mont. 352, 354 P.3d 631 (citing Denke v. Shoemaker, 2008 MT 418, ¶ 39, 347 Mont. 322, 198 P.3d 284 (stating that Montana courts review an agency's interpretation of law for correctness)).

Although we give deference to the interpretation given a statute by the officers or agency charged with its administration, this does not mean that courts must rubberstamp any interpretation the agencies may give a statute. Rules of statutory construction have no application if the language of the statute is clear and unambiguous. It has always been our rule that it is the province of the courts to construe and apply the law as they find it and to maintain its integrity as it has been written by a coordinate branch of the state government. When the terms of the statute are plain, unambiguous, direct and certain, it speaks for itself and there is no room for construction. Bay v. Dep't of Admin., Pub. Employee's Retirement Div., 212 Mont. 258, 265, 688 P.2d 1, 4 (1984).

The construction of a statute by the person or agency responsible for its execution should be followed unless there are compelling indications that the construction is wrong. D'Ewart v. Neibauer, 228 Mont. 335, 340, 742 P.2d 1015, 1018 (1987).