New York Court Orders NYDEC to Issue Climate Change Regulations by February 2026

On October 24, 2025, a New York trial court ordered the New York Department of Environmental Conservation (NYDEC) to promulgate regulations addressing climate change pursuant to the state’s 2019 Climate Leadership and Community Protection Act, 2019 N.Y. Sess. Laws Ch. 106 (S. 6599) (CLCPA). The court sided with environmental groups that argued that NYDEC’s failure to issue these rules violated a mandatory statutory duty, despite the agency’s arguments that such rules would be “infeasible” because of costs imposed on consumers. With the order requiring promulgation of the rules by February 6, 2026—mere months away—stakeholders should watch closely for details on upcoming compliance requirements.

Background

The CLCPA, enacted in 2019 and effective 2020, set ambitious statewide goals to reduce greenhouse gas emissions 40% by 2030 and 85% by 2050, compared to 1990 levels. To achieve these mandates, the statute established a Climate Action Council, a statewide body charged with developing a “Scoping Plan” to act as a roadmap to cut greenhouse gas emissions. The CLCPA also directed NYDEC to promulgate regulations by January 1, 2024, to ensure that the state reached the statutory reduction thresholds. The regulations were to include legally enforceable emissions limits and performance standards across all industries except livestock.

While NYDEC engaged in rulemaking efforts such as public workshops in 2023 and 2024, the agency ultimately failed to issue the required regulations—draft or final—throughout 2024, despite recommendations published in 2022 under the Scoping Plan developed by the Climate Action Council. Rather, in early 2025, the Governor announced the development of greenhouse gas reporting requirements, and NYDEC subsequently published draft regulations in late March. However, the agency did not provide information or a timeline for rulemaking for emissions limits or other emissions reduction programs, such as a cap-and-invest program.

Environmental groups—including Sierra Club, Citizen Action of New York, WE ACT for Environmental Justice, and People United for Sustainable Housing Buffalo—filed a complaint in the New York Supreme Court–Albany County in March 2025, alleging that the agency’s delay violated both the CLCPA and the New York Constitution’s Environmental Rights Amendment. The suit sought injunctive relief for NYDEC to promulgate the regulations and declaratory relief for the constitutional violation.

The Court’s Decision

The court granted the petitioners’ request for a mandatory injunction compelling NYDEC to promulgate emissions reduction regulations under the CLCPA. The court found that the CLCPA’s directive that NYDEC “shall … promulgate” regulations was unambiguously mandatory and left the agency no discretion to decline action due to policy concerns or fiscal burden.

The court rejected NYDEC’s argument that implementation was “infeasible” because it would impose “extraordinary and damaging costs upon New Yorkers.” The court held that determining feasibility or affordability “is beyond the scope of [NYDEC’s] authority under the Climate Act,” since the Legislature—not the agency—had already decided that the mandated emissions reductions “‘shall’ be achieved.”

While acknowledging the complexity of the regulatory task, the court noted that the agency “does not have the discretion to say no or to decide that it has the authority to choose not to follow the express legislative directive at issue.” It emphasized that if NYDEC believes the goals are unattainable, it must seek relief from the Legislature, not unilaterally disregard the law.

The court ordered NYDEC to promulgate regulations shortly after the next legislative session begins in January 2026, and thus set a deadline of February 6, 2026. The court expressly declined to opine on the constitutional issue.

Key Takeaways

• NYDEC must issue climate regulations by February 6, 2026—which is just three months away.
• Cost of implementation, if not expressly allowed by the Legislature as a consideration, cannot override a statutory mandate to regulate climate change.
• This decision may accelerate development of a cap-and-invest program, a key mechanism outlined in the Climate Action Council’s Scoping Plan.

This decision represents a significant step toward enforcing New York’s climate commitments under the CLCPA. Stakeholders should closely follow NYDEC’s rulemaking process in the coming months, as the resulting regulations will shape the state’s greenhouse gas compliance framework for decades to come.

This post is as of the posting date stated above. Sidley Austin LLP assumes no duty to update this post or post about any subsequent developments having a bearing on this post.