Johan Galtung, in a 2016 editorial titled "Charlatanism: 'The Positive Peace Index'", argued that the IEP's framework omits structural violence and accordingly classifies "societies-regions-worlds so repressive that violence is not needed" as peaceful.^[11] In his earlier papers, he defined positive peace and negative peace, as well as the concept structural violence. He and other researchers considered economic blockades and sanctions an insidious form of structure violence.^[12][13]

Extending this line of criticism, peace researchers Peter T. Coleman and Kyong Mazzaro identified in 2013 a fundamental measurement asymmetry in the GPI: both the original GPI and the later Positive Peace Index (PPI) overwhelmingly measure the absence of negative conditions rather than the presence of positive ones.^[14] A coding of the PPI indicators found that 73 per cent measured negative conditions (e.g., crime victimisation, homicide rates, perceived discrimination) while only 27 per cent assessed positive ones; combined with the GPI, the negative-to-positive ratio approached 7:1. Coleman and Mazzaro argued that decades of research in peace psychology, including John Gottman's findings that the predictors of divorce and the predictors of marital happiness are qualitatively distinct, and the authors' own studies of Israeli and Palestinian motivations, demonstrate that the drivers of sustainable peace are fundamentally different from the inverse of the drivers of violence. They proposed that sustainable peace be measured through a framework that tracks both the decreasing probability of destructive conflict and the increasing probability of cooperation, justice, and well-being, drawing on evidence that social systems thrive when the ratio of positive to negative dynamics exceeds approximately 3:1 to 5:1.^[14]

A second concern raised by the same authors is the GPI's dominant economic lens. They observed that roughly half of the PPI's indicators are linked to the IEP's concept of a "Peace Industry" (metrics such as economic growth, consumer spending, and sound business environment) and noted that while commercial liberalism shows some correlation with reduced interstate conflict, economic openness does not significantly reduce internal conflict. Research indicates that horizontal inequalities (the intersection of political, social, and economic disparities) are a better predictor of civil rebellion than income level alone.^[14]

Bell and Mo, in proposing their Harmony Index as an alternative, argued that the GPI suffers from an individualist bias that downplays key social relations for human well-being. Their analysis found that the GPI provides no discussion of the kinds of family structures conducive to social peace, and no systematic treatment of environmental challenges—such as competition over water resources between India and China—that threaten peace within and between countries. They contended that any index of well-being should measure a society's ability to provide peaceful conditions for its people through rich and diverse social relations.^[15]

Observations from a 2010 seminar on measuring peace, convened by the International Catalan Institute for Peace (ICIP), noted that the GPI's expert panel debated how to include what is not measured—such as violence by men against women, or the degree of social cohesion within a society—but lack of data on positive elements of peace posed a persistent obstacle. According to the proceedings, when the option of including a positive indicator was raised, the Economist Intelligence Unit—which provides the qualitative assessments for the GPI—responded that no data were available. The GPI's vice-president acknowledged at the seminar that results for very small countries, such as Iceland, could be misleading in comparison with those of much larger countries.^[16]

Critics argue that if peace is defined more by circumstances such as living in more remote, isolated or island regions, instead by positive, harmonious or proactive human actions such as conflict resolution and governance, then the value of a universal ranking metric across all nations would be reduced.^{[17][14][15][18]} Dr. Mayank Chaturvedi suggests a more equitable model peace index that would be population-adjusted, with greater emphasis on institutional strength regarding elections, the judiciary, press freedom, as well as on maintaining peace amidst religious or cultural diversity, and challenges in areas of security, economic opportunity and social mobility.^[17]

The methodology used to construct and rank the Global Peace Index does not deal with positive peace. In addition, it may face criticism due to the following:

• Reproducibility issue: five of the 23 indicators are not measured but are qualitative judgments assigned by anonymous analysts; many of the remaining 18 quantitative indicators depend on internally imputed values. Because the scoring practices of these analysts and imputation procedures are not fully disclosed, independent researchers cannot reproduce or verify these scores, effectively making the index a "closed-source human model". Relatedly, the GPI operates at the national level of analysis, which—while feasible for a global index—neglects significant sub-national variation in peacefulness across regions, communities, and cities, and relies on data from countries that may lack the basic infrastructure to collect accurate statistics on the measured indicators.^[14]
• False statistical precision and ranking artefacts: The GPI reports scores to three decimal places without any quantification of uncertainty or confidence intervals, importing more precision than the underlying data (such as estimated conflict deaths or subjective estimate of political stability) can support.^[19]
• Subjective or somewhat arbitrary selection or weighting of the factors:^[18] In computing the index, relevant factors (for the instigators) are not meaningfully counted, such as imposition of economic blockade or sanctions that negatively impact human development or regional stability, troops stationed or deployed abroad for war preparations, assassinations conducted in neighboring countries, participation in foreign regime changes, proxy wars, and covert actions. Nair noted in 2016 that small, stable and democratic countries are most peaceful according to GPI, and most of them are western or central European democracies.^[20] Swanson noted in 2022 that five of the 10 most “peaceful” nations on Earth were NATO members.^[18]

The 2026 GPI report includes some 2026 data, but most indicators draw on data from 2025 or earlier. Although the report mentions the Iran War (which began on 28 February 2026) dozens of times across multiple chapters^[21] and includes a dedicated subchapter on its economic impact,^[22] the Index itself does not fully capture this conflict. The report notes that "the full impact of the Iran war is not captured by the Index this year"^[5] and that Israel's improvement "does not take into account the Iran war that started in late February 2026".^[23] Country-level relations indicators are updated only to the end of March 2026, leaving most 2026 events outside the scoring window.

It is also often not clear which data are obtained from direct surveys and which from imputation. Appendix A states that IEP uses "multivariate imputation by chained equations to create country-level estimates" when official data are missing,^[24] but the assumptions underlying these imputations—particularly the missing-data mechanism (MCAR, MAR, or MNAR)—are not explicitly discussed in the main body of the report.

Despite devoting a full chapter to the "Economic Impact of Violence",^[25] none of the 23 GPI indicators directly measures human injuries, suffering, or the direct economic cost of war (such as infrastructure destruction or conflict-related healthcare expenditure). The Index instead operationalises peace as the absence of violence through structural and institutional indicators (military expenditure, weapons transfers, political stability, etc.). As a result, a country can be actively engaged in sustained military conflict yet still register an overall score improvement if other indicator domains move favourably.

The 2026 GPI illustrates this limitation: Israel's overall score improved by 2.6 per cent,^[23] driven mostly by improvements in the Militarisation domain and selected conflict indicators,^[23] even as the country remained engaged in the protracted Gaza campaign (entering its third year), the June 2025 Twelve-Day War with Iran, and renewed conflict with Hezbollah in early 2026.^[26] The human costs—including tens of thousands of civilian casualties^[27][10] and large-scale infrastructure damage—fall largely outside the 23-indicator framework. In the same report, China's ranking dropped by 11 positions while the country was not engaged in any active armed conflict during the scoring period, illustrating how the index's structural and institutional focus, combined with its weighting scheme, can produce rankings that appear counterintuitive when assessed against a country's actual involvement in armed conflict. Some observers have noted that the methodology may systematically favour small, isolated, and homogeneous nations over larger, heterogeneous countries with complex geopolitical settings and histories.^[15][16]

Further research would be needed to see to what degree Global Peace Index may be susceptible to the common problems associated with composite index, such as arbitrary weightings, false precision, inconsistent standards, hidden methodologies, misleading comparisons.^[19] Global Peace Index 2026 itself did not mention if uncertainty analysis and sensitivity analysis have been performed as advised by OECD Handbook on Constructing Composite Indicators^[28][29] to test robustness of the index across the 163 countries.

In 2021, Thomas Morgan of the Institute for Economics and Peace published a systematic defence of the GPI's methodology, addressing several composite-indicator criticisms directly.^[30] According to IEP, the decision to measure negative peace rather than a broader positive-peace construct is deliberate: negative peace—defined in the Galtungian tradition as the absence of violence or fear of violence—provides a concept narrow enough to be operationalised with available cross-national data, while the GPI's maximalist approach of combining 23 indicators across three domains (Safety and Security, Ongoing Conflict, and Militarisation) is designed to prevent scores from being skewed by high peacefulness in one domain at the expense of another.

Regarding the qualitative indicators, IEP states that the qualitative assessments are scored by Economist Intelligence Unit country analysts, reviewed by regional directors, and subjected to further scrutiny by the GPI's expert panel.^[30] On the issue of weighting and aggregation, Morgan acknowledges that no purely objective method of constructing a composite index exists—even data-driven techniques such as principal component analysis require a subjective decision to treat variance as a proxy for importance. The GPI therefore relies on expert panel judgment to determine indicator weights, and uses linear aggregation as its default method.^[30]

IEP reports that robustness testing has been conducted on the GPI, drawing on the framework of the OECD Handbook on Constructing Composite Indicators. Morgan notes that while there is no universally accepted robustness threshold beyond which an index can be considered reliable, lower levels of robustness signal that a composite is particularly sensitive to the choice of weights and aggregation method. IEP has indicated that constructing alternative versions of the GPI using geometric rather than linear aggregation—and comparing the resulting country rankings—is an area of planned future methodological review.^[30]

On the omission of specific indicators, IEP has acknowledged that violence against women and violence against children were excluded from the GPI primarily because comparable cross-national data are not collected at sufficient frequency for the required number of countries. Morgan notes that the USAID Demographic and Health Surveys collect data on intimate partner violence, but these surveys are conducted infrequently and primarily in less economically developed countries. IEP has stated that should higher-coverage data become available, the GPI could be expanded to include an indicator of gender-based violence.^[30] Regarding self-directed violence, IEP argues that no consensus exists in the peace and conflict field on whether suicide should be classified alongside interpersonal or state-based violence, though the question remains open. The GPI's terrorism indicator, originally a qualitative assessment, was upgraded in 2012 to a quantitative measure using the Global Terrorism Database (GTD), incorporating the number of terrorist events, deaths, injuries, and property damage, weighted over a five-year period and normalised with an exponential function to reflect the enduring psychological impact of attacks.³⁰