Ruth Bader Ginsburg's death and the battle over her vacant Supreme Court seat have real implications for energy and climate policy.

Why it matters: If President Trump replaces her, the court will likely become more skeptical of regulations that claim expansive federal power to regulate carbon under existing law, and perhaps new climate statutes as well.

• If Joe Biden wins the election, that expanded conservative majority on the court could create more legal jeopardy for his promised initiatives to strengthen emissions regulations and create new major ones.
• "[A] Biden Administration could find it harder to demonstrate that it had a 'reasoned explanation' for rewriting final, Trump-era rules," ClearView Energy Partners said in a weekend note.
• If Trump wins again, it could strengthen his hand in defending his moves to scrap or weaken Obama-era policies.

The big picture: SCOTUS already blessed federal regulation of greenhouses gases in a 2007 decision, but how much running room it gives agencies is another question entirely. A huge thing in regulatory litigation is how justices interpret the 1984 high court ruling in Chevron v. Natural Resources Defense Council. It gives agencies leeway to interpret statutes that are vague or silent on a topic.

What they're saying: "Already, the Court has been taking a narrower view of Chevron — finding that it applies in fewer and fewer instances, so the principle of deference to agency expertise seems to apply to a smaller scope of cases," said Harvard Law professor Jody Freeman."So, this was already the direction, and a Biden administration was already going to have to be smart and strategic about regulation," said Freeman, who worked in Obama's first-term White House.

Yes, but: "Biden could do a lot on climate change within the EPA’s well-established authority to reduce greenhouse gases," Freeman said, adding, "There is plenty of room to make substantial progress using executive power, while controlling legal risk."

Our thought bubble: There's an even bigger potential spillover effect from the fight over the vacant seat.

• Imagine Trump loses and Democrats also take the Senate, but the current GOP Senate majority confirms his SCOTUS pick this year.
• If that happens, the odds grow that Democrats would scrap filibuster rules next year to make it easier to implement their agenda.
• That, in turn, greatly increases the odds of passing big climate and energy legislation, which faces immense hurdles with the 60-vote threshold intact.

The intrigue: Per ClearView, ending the filibuster would have multiple spillover effects.

• "[T]he legislative filibuster does not merely shelter the fossil energy status quo by raising the bar for passage."
• "It also gives a 41-Senator minority the power to threaten a government shutdown (i.e., by blocking funding packages) as a check against Executive Branch decisions. That check would disappear."