Notwithstanding the established death toll of 2,975 people in Puerto Rico from Hurricane Maria, President Trump persists in asserting that it is limited to double digits. But Trump is hardly the first national leader to prevaricate when it comes to the consequences of extreme weather. World leaders lie about the costs and consequences of extreme weather and climate change because they are motivated to do so, and—with the exception of blatantly false statements like Trump’s—their lies are difficult to expose.

The motive rests in the powerful repercussions of climate change, and the cost of addressing them. As a result of climate change, the world is dealing with rising sea levels, temperature increases and heat waves, intense storms, hurricanes and cyclones, sea acidification, melting glaciers, extreme drought and far-reaching changes to ecosystems that can cause species extinction.  The human impacts of climate change include loss of lives, homes, and infrastructure due to flooding, storms and sea level rise, health impacts due to temperature increases that spread disease, hunger due to crop damage and new pests, and loss of access to clean drinking water due to drought. This is heavy stuff, resulting in outcries and demands for accountability from local and national leaders; the post-earthquake uproar in Indonesia following the revelation that none of the twenty-two buoys spread over Indonesia’s open water to help monitor for tsunamis had been operational for the past six years is but one instance.

The effects of climate change can also trigger financial obligations pursuant to the United Nations Framework Convention on Climate Change (UNFCC). The price tag of slowing down climate change by reducing emissions, primarily through investing to construct wind and solar power facilities and to protect the world’s forests, is about US$300–400 billion per year. A fundamental feature of the UNFCC is “climate finance,” money drawn from public and private sources of financing that seeks to support mitigation and adaptation actions to address climate change.

The “polluter pays principle” of the UNFCC means that industrialized nations— who have historically contributed the most to global warming—should compensate developing countries for climate change’s damaging effects, as well as the costs of mitigating and adapting to them. Upon signing the UNFCC in 1992, developed countries (including the United States) agreed to provide significant financial support for mitigation and adaptation action in developing countries. The Paris Agreement of 2016 finalized targets for finance and emission reductions. The United States is a party to the UNFCC. However, on June 1, 2017, it withdrew from the Paris Agreement and ceased to implement its terms, including the Nationally Determined Contributions and financial contributions.

Examples abound of “polluters” who are motivated to conceal the extent of environmental damage for which they are responsible. For instance, China quietly acknowledged in 2015 that it had been using up to 17% more coal a year than reported. By some estimates, that means almost a billion more tons of carbon dioxide released annually. In addition to underreporting, another method of concealment is quid pro quo corruption; polluters may attempt to avoid paying under the carbon offset framework by bribing those determining country contributions. With two consenting parties to the bribe, such corruption is difficult to expose.

Not only is the amount of money involved in climate finance enormous, but the path it travels from donor to recipient is complex. To get climate finance off the ground, the United Nations (UN) has created the Green Climate Fund, a clean energy investment vehicle. This fund and others like it do not channel funding directly to recipient countries, but rather through a bevy of banks and UN agencies, as well as national level actors.

As shown by the Volkswagen “diesel dupe,” increased regulation in the realm of pollution can lead to fraud and corruption to avoid it. Where there are significant amounts of public funding available, there is greater risk of corruption in the administration of those funds. Moreover, detection in a complex regulatory setting is all the more difficult. When hundreds of millions of climate finance dollars flow in a circuitous route from donor to recipient countries, the risk of climate funds being frittered away pursuant to fraud, waste or abuse is unavoidable.

How to guarantee truth in the causes, costs and consequences of climate change? First, climate finance must be transparent. It is imperative to be able to track climate finance flows and advocate for stronger protections to ensure that efforts to adapt to and mitigate the impacts of climate change are not hampered by corruption. Implementation of the Paris Climate Change Agreement is key to transparency, as the Agreement’s implementation guidelines are needed to unlock transparent and practical climate action across the globe, including finance, technology and capacity building. The implementation guidelines have been under negotiation since 2016, and they are set to be adopted at the 24th annual Conference of Parties to the UNFCC (COP24), to be held in Poland in December of 2018.

Second, climate finance must be accountable. Corruption and mismanagement must be, if not prevented in the first instance, then exposed and addressed. The Green Climate Fund has an internal body that investigates allegations of fraud and misconduct; this is necessary, but insufficient. Parties to the UNFCC must commit investigative and legislative resources to addressing corruption in the realm of the environment in their own countries.

An era of climate change and extreme weather has arrived. It is incumbent on heads of state and parties to the UNFCC to adapt to this era and seek to mitigate its effects. Transparency and accountability are essential in stemming the damage caused by climate change. Nothing less than life as we know it hangs in the balance.

Juliet S. Sorensen is a Clinical Professor of Law and the Director of the Bluhm Legal Clinic at Northwestern Pritzker School of Law. She is the author of Public Corruption and the Law: Cases & Materials (West Academic 2017) (with David Hoffman) and Corruption in an Era of Climate Change: Rebuilding Sint Maarten After Hurricane Irma (Small Island Developing States Research Platform 2018) (with Cindy Gerges, Gerry Hirschfeld, Claire Hutar, Elise Meyer, and Garrett Salzman).