The courts in this case are interpreting the constitution of the state of Montana, which was written and ratified by the legislature. Quoted below: Constitutio

The courts in this case are interpreting the constitution of the state of Montana, which was written and ratified by the legislature. Quoted below: Constitution of Montana -- Article IX -- ENVIRONMENT AND NATURAL RESOURCES Section 1. Protection and improvement. (1) The state and each person shall maintain and improve a clean and healthful environment in Montana for present and future generations. (2) The legislature shall provide for the administration and enforcement of this duty. (3) The legislature shall provide adequate remedies for the protection of the environmental life support system from degradation and provide adequate remedies to prevent unreasonable depletion and degradation of natural resources.