Ninth Circuit affirms dismissal of PacifiCorp's challenge to Washington decarbonization rules

The Ninth Circuit Court of Appeals confirmed a Washington federal court’s decision to dismiss PacifiCorp’s lawsuit challenging the state’s decarbonization enforcement. PacifiCorp alleged that the Department of Ecology’s application of the Climate Commitment Act violated the dormant commerce clause. Because the utility receives no-cost carbon allowances for electricity sold to Washington customers, it needed to show that similarly situated parties were treated differently, which it did not.

The appellate judges deemed the claim unconvincing and upheld the lower court’s dismissal. This ruling validates Washington’s climate-related regulatory framework and underscores the legal hurdles faced by utilities contesting state climate measures.