In international law, odious debt, also known as illegitimate debt, is a legal theory that holds that the national debt incurred by a regime for purposes that do not serve the best interests of the nation, should not be enforceable. Such debts are, thus, considered by this doctrine to be personal debts of the regime that incurred them and not debts of the state. In some respects, the concept is analogous to the invalidity of contracts signed under coercion.
The doctrine of odious debt was formalized in a 1927 treatise by Alexander Nahum Sack, a Russian émigré legal theorist. It was based on two 19th century precedents—Mexico's repudiation of debts incurred by Emperor Maximilian, and the denial by the United States of Cuban liability for debts incurred by the Spanish colonial regime.
When a despotic regime contracts a debt, not for the needs or in the interests of the state, but rather to strengthen itself, to suppress a popular insurrection, etc, this debt is odious for the people of the entire state. This debt does not bind the nation; it is a debt of the regime, a personal debt contracted by the ruler, and consequently it falls with the demise of the regime. The reason why these odious debts cannot attach to the territory of the state is that they do not fulfil one of the conditions determining the lawfulness of State debts, namely that State debts must be incurred, and the proceeds used, for the needs and in the interests of the State. Odious debts, contracted and utilised for purposes which, to the lenders' knowledge, are contrary to the needs and the interests of the nation, are not binding on the nation – when it succeeds in overthrowing the government that contracted them – unless the debt is within the limits of real advantages that these debts might have afforded. The lenders have committed a hostile act against the people, they cannot expect a nation which has freed itself of a despotic regime to assume these odious debts, which are the personal debts of the ruler.
There are many examples of similar debt repudiation.
Patricia Adams, executive director of Probe International, a Canadian environmental and public policy advocacy organisation and author of Odious Debts: Loose Lending, Corruption, and the Third World's Environmental Legacy, stated: "by giving creditors an incentive to lend only for purposes that are transparent and of public benefit, future tyrants will lose their ability to finance their armies, and thus the war on terror and the cause of world peace will be better served." In a Cato Institute policy analysis, Adams suggested that debts incurred by Iraq during Saddam Hussein's reign were odious because the money was spent on weapons, instruments of repression, and palaces.
A 2002 article by economists Seema Jayachandran and Michael Kremer renewed interest in this topic. They propose that the idea can be used to create a new type of economic sanction to block further borrowing by dictators. Jayachandran proposed new recommendations in November 2010 at the 10th anniversary of the Jubilee movement at the Center for Global Development in Washington, D.C. Thereupon, the loan sanctions model has been adapted by the Centre for Global Developments  and has been the base for a number of further suggestions.
In December 2008, Ecuadorian President Rafael Correa attempted to default on Ecuador's national debt, calling it illegitimate odious debt, because it was contracted by corrupt and despotic prior regimes. He succeeded in reducing the price of the debt letters before continuing paying the debt.
After the overthrow of Haiti's Jean-Claude Duvalier in 1986, there were calls to cancel Haiti's debt owed to multilateral institutions, calling it unjust odious debt, and Haiti could better use the funds for education, health care, and basic infrastructure. As of February 2008, the Haiti Debt Cancellation Resolution had 66 co-sponsors in the U.S. House of Representatives. Several organizations in the United States issued action alerts around the Haiti Debt Cancellation Resolution, and a Congressional letter to the U.S. Treasury, including Jubilee USA, the Institute for Justice & Democracy in Haiti and Pax Christi USA.
- Debt relief
- Debt of developing countries
- Jubilee USA Network
- Haiti's external debt
- Moral hazard
- Sovereign debt
- Sovereign default
- Domestic Liability Dollarization
- Robert Howse (July 2007). The Concept of Odious Debt in Public International Law (PDF). Geneva: UNCTAD.
- Graeme Smith (20 November 2011), "A new euro crisis strategy: Deny the debt", The Globe and Mail
- Mitu Gulati; Sarah Ludington; Alfred L. Brophy (January 2010). "Applied Legal History: Demystifying the Doctrine of Odious Debts". Theoretical Inquiries in Law (Walter de Gruyter GmbH) 11 (1): 247–281. doi:10.2202/1565-3404.1242. ISSN 1565-3404.
- Patricia Adams (1991). Odious Debts: Loose Lending, Corruption, and the Third World's Environmental Legacy. ISBN 978-1853831225.
- Patricia Adams, "Iraq's Odious Debt", Cato Institute
- Michael Kremer; Seema Jayachandran (Spring 2003). "Odious Debt: When Dictators Borrow, Who Repays the Loan?". Brookings Institution.
- Michael Kremer; Seema Jayachandran (June 2002). "Odious Debt". Finance & Development (IMF) 39 (2).
- Schneider, Friedrich Benjamin (2015). "The International Convention on the Prevention of Odious Agreements: A Human Rights-Based Mechanism to Avoid Odious Debts". Leiden Journal of International Law (Cambridge University Press) 28 (3): 557–578.
- "Ecuador defaults on foreign debt". BBC. 13 December 2008.
- "'Avenger against oligarchy' wins in Ecuador", The Real News, 27 April 2009.
- Haiti Debt Action
- "Congresswoman Maxine Waters Introduces Legislation to Cancel Haiti’s Debt"
- "Institute for Justice & Democracy in Haiti". Ijdh.org. 2008-02-12. Retrieved 2012-10-23.