Passing transformative climate change legislation through the U.S. Congress will be one of the major legislative battles of this decade. While climate measures should have a dramatic impact on the economy, particularly the energy sector, for years to come, its prospects of success and final composition will be impacted by a tactic that was first used in 1837 – the filibuster.

The Life of a Tactic

A filibuster occurs in the U.S. Senate when a senator, or group of senators, try to block or delay a vote on a measure such as a piece of legislation. Members start speaking on any topic, attempt to extend debate and force the other side to give up efforts to pass the measure and move on to other business.  Senators can do this because the Senate’s rules allow members to speak as long as they want unless three-fifths of Senate votes to end debate.  The vote to stop debate is called invoking cloture and currently requires 60 votes to be passed.  Once cloture is in place the measure can be brought up for a vote.

This tactic works because while debate in the Senate can be unlimited, the reality is that Congress operates on a two-year schedule.  If a piece of legislation is not passed by the end of the second year it has to start all over when the new Congress convenes the following year.  The filibuster forces leadership to abandon efforts to pass legislation that they know will not get enough votes for cloture or risk wasting time that could be used trying to pass more popular measures.

The effectiveness of the filibuster is demonstrated by the fact that its use has increased steadily over the last few decades, even as the leadership of the Senate chamber has changed hands.

Climate Change and the Filibuster

One area where the tactic has been used is in the fight to stop climate change legislation. In 2008, the Lieberman-Warner cap and trade bill was defeated, despite bipartisan support and the backing of both parties presidential nominees, when the Senate was unable to pass a cloture motion and stop the filibuster. Just two years later the Democratic leadership in the Senate would not even bring another cap and trade measure to floor because they knew they could not win a cloture vote.

Even though polling shows there is great public concern about climate change, there are similar fears that the filibuster will be used on to stop legislation that mandates cuts in carbon emissions.  The worry that efforts on climate change and other issues will be blocked has prompted some elected officials and activists to call for the elimination of the filibuster.  Instead of requiring 60 votes to stop debate, it would only require a simple majority of 51 Senators to stop debate and move legislation forward.

This would be a significant change. It would have such a profound effect on the types of legislation that are put forward and passed that even talk of eliminating the filibuster has been referred to as the nuclear option by legislators and pundits in Washington, DC.

To underscore this point, consider that the need to get 60 votes to move a bill forward means that legislation needs broad support. Under most circumstances that means bipartisan votes. The need to garner Republican votes will shape the content of climate legislation.

Current polls show around 65 percent of the public says the government is doing too little to reduce the effects of climate change.  The same polling shows members of both parties support the federal government taking on climate change by spending money or giving tax credits to develop carbon capture technology.  However, Republican support falls when measures such as tougher restrictions on power plant emissions, implementing a tax on carbon, and higher fuel-efficiency standards are introduced.

Based on these findings, if climate legislation is to go through Congress under the current rules, it is likely to include substantial funding for carbon sequestration and would need to include compromises on items such as a carbon tax or other ways to limit emissions.  Considering what has happened in the past, it is hard to see the Senate passing a more wide-reaching bill, such as cap and trade or ambitious emissions reduction targets, with the filibuster in its present form.

In contrast, if legislation only needs 51 votes to pass through the Senate the incentive to build a widespread coalition is diminished.  A simple majority could push for a more ambitious program to deal with climate change.

For example, if the Democrats took control of the Senate in November, they might push for a carbon tax, cap and trade, or elements of the Green New Deal, which are very popular with their activists and Democratic voters.  Any of these changes would have significant implications for industry, investors, and the speed of the energy transition.

The future is now

Currently, the future of the filibuster is uncertain.  Earlier this year several candidates endorsed the idea of eliminating the procedure.  Whether that is just campaign talk, or the start of a major legislative change remains to be seen.  That question will not be answered until we know the results of the November election.

What is clear is that the rules in place will have a significant impact on what, if any, climate legislation is passed by the U.S. Congress.