Our annual round-up about global climate legislation delivered at the United Nations Framework Convention on Climate Change intersessional conference in May shows that there is a stock of 1200 laws in the 164 countries now covered by the Climate Change Laws of the World database. This is a twenty-fold growth in the number of laws relating to climate change since 1997, when the Kyoto Protocol was signed.

The analysis also showed that since the Paris Agreement was signed at COP21 in December 2015, 47 new laws and policies relating to climate change have been introduced. Of the new laws, 4 relate to ‘nationally determined contributions’ (NDCs).

Whilst it is good news that some countries have started to legislate for the emissions reductions they have pledged, not all signatories have legislative support for their targets – but they are likely to need it if they are collectively to ratchet up emissions reductions in order to keep global warming to well below 2°C.

However, recent developments in the United States cast a cloud over the proceedings in Bonn. President Trump’s administration is due to make a decision after the G7 summit in Italy later this month about whether to trigger the 4 year process to pull the United States out of the Paris Agreement – something Mr Trump promised during his campaign.

The new administration are said to be divided on the issue. Some advocating for a withdrawal from Paris have reportedly warned that trying to reduce targets for emissions cuts could end in court proceedings, with green groups filing law suits against the Government. Others have pointed out that the NDCs of signatories to the Paris Agreement are not legally binding and can be revised either up or down without the risk of litigation.

The number of court cases relating to climate change and climate action is increasing

Nevertheless, our analysis shows that there has been an upsurge in recent years in the number of legal disputes over actions – or inaction – related to climate change mitigation and adaptation efforts.

The database of Climate Laws of the World this year, for the first time, includes climate-related litigation, covering more than 250 court cases across 25 jurisdictions. The United States is not included in the database. A parallel database, with more than 700 entries, is maintained by the Sabin Center at Columbia University and Arnold and Porter Kaye Scholer LLP.

The earliest entry in the climate litigation database is an Australian case from 1994 in which Greenpeace challenged the approval of a power station in the Hunter Valley on the basis that there was no demand for the new power station and that it contradicted both Australian and international policies to reduce greenhouse gas emissions. The Court ruled that the law did not restrict the building of new power stations and the appeal was dismissed.

From the first case in 1994 until mid-2000s there were few new cases relating to climate change, but since then there has been a significant rise – there have been at least 10 per year in the jurisdictions covered in the database.

Litigation can help action on climate change…

Lawsuits can be used to strengthen climate action by pressing policy-makers to be more ambitious, holding them to account, or filling a gap left by insufficient legislation or inaction. In the United States, the lack of a comprehensive legislation means that litigation has played a particularly important role in tackling climate change.

To mention a recent example, referred to as ‘the Juliana case’, 21 young plaintiffs aged between 8 and 19 have taken legal action, alleging that the defendants (the United States Government) “deliberately allow[ed] atmospheric CO2 concentrations to escalate to levels unprecedented in human history”, which threaten the plaintiffs’ fundamental constitutional rights to life and liberty. The case could, if successful, force stricter regulation of carbon dioxide emissions.

…and also hinder it

Litigation can also work in the other direction. A substantial number of anti-regulatory cases seek to delay, limit, or invalidate climate regulatory actions.

For example, Scott Pruitt, as attorney general of Oklahoma, took the United States Environmental Protection Agency to court 14 times seeking to push back regulation on pollutants and emissions, including an action against the Clean Power Plan. On 9 February 2016, the United States Supreme Court had ordered a stay of the Plan until a decision is made on a pending court case against the Agency. Mr Pruitt is now the administrator of the Agency in President Trump’s administration.

Litigation on climate change is usually brought by corporations and usually the Government are in the dock

Corporations, government agencies, non-governmental organisations and individuals can take, or can be taken to, court.

Our snapshot of global climate laws and litigation in the 25 jurisdictions shows that the most common plaintiffs are corporations (40% of the cases), and that most of the time governments are the defendants (79% of the cases). Corporations are the second most common defendants, in 13% of cases.

Previous research also suggests that in the United States the government has been the defendant in the majority of cases relating to climate change. Out of the 201 cases filed up until 2010, governments (federal, state and/or municipal) were named as defendants or co-defendants 204 times – sometimes more than one government was named as a co-defendant in a single case. Corporations were defendants in 45 cases. By contrast, 141 out of the 201 cases were launched by environmental NGOs, while industry NGOs and companies each started 27 actions.

Two-thirds of cases strengthen or preserve existing climate change regulations

Although most of the cases studied outside the United States are brought by corporations, likely seeking to push back climate related regulations, the majority of cases either strengthen or preserve climate action.

Out of a total of 241 cases analysed in the new study, the verdicts for 135 enhanced climate regulation and 24 were neutral – neither enhancing nor limiting. In 85 cases, the rulings hindered tighter climate policies. 12 cases are still ongoing.

Similar findings resulted from the study by Markell and Ruhl of court cases in the United States – in 161 of the 201 cases filed by 2010, litigation increased regulation or liability associated with climate change.

The courts will play an increasing role in achieving the Paris Agreement

We have yet to understand which factors influence the outcomes of cases relating to climate change and how they vary between countries.

There is also no clear pattern between the number of climate laws adopted in a country and the number of court cases filed. Our latest analysis shows that in Canada, New Zealand and Australia litigation is increasing whereas legislative activity has plateaued. In Spain, the situation is the other way round. In the UK, Brazil and India, legislation and litigation are both growing.

For now, the verdict of the courts is overall helping action on climate change, but it is not clear what the future impact of the courts will be. There have been increasing numbers of ongoing and new cases each year up to 2017 and it is likely that that trend will continue with the courts complementing the work of legislators in tackling climate change.

With a large stock of 1200 climate change laws now in place globally, countries have the foundations to build further climate action on. The challenge for the future will be in strengthening existing laws and filling gaps – and the courts can play an effective role in achieving that.

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