placestats

Pre-trial detainee share vs. Redistribution

Holds up after adjusting for income

Across 43 countries, Pre-trial detainee share and Redistribution rise and fall together at r = -0.44 (on a scale from −1 to +1, where 0 means no link). It holds up almost unchanged when only countries with similar income (GDP per person) are compared (r = -0.44, q = 0.028, allowing for the many pairs tested).

Comparing countries across the middle half of redistribution, 24.6% to 38.4% reduction in the Gini, pre-trial detainee share is better by 7.2% of prisoners at the top of that range than the bottom. Comparing only countries with similar national income, the gap is 9.09% of prisoners.

Link before adjusting (r)-0.445p = 0.003 · 43 countries
After adjusting for national income-0.442p = 0.003 · likely range [-0.66, -0.16]
p, allowing for regions0.001standard error 0.071 · 7 regions
Check for luck (q)0.028across 12,497 pairs

How to read these.r runs from −1 (one goes up as the other goes down) to +1 (they rise together), and 0 means no link. Adjusting for national income means comparing countries with the same GDP per person, so differences in wealth can’t explain the link. Income is used in percentage terms, since an extra $1,000 means more to a poor country than to a rich one. p is how likely a link this strong would be if there were really none. Below 0.05 means it is unlikely to be chance. Very small values are written in short form: 1.1e-32 means a decimal point followed by 31 zeros and then 11, so very close to zero. The likely range is where the true figure probably lies, and a range that crosses zero means the link could easily be chance. Countries in the same region tend to resemble each other, so the third figure allows for that, which gives a fairer p. The standard error is the typical size of the error in r. Finally, testing this many pairs means some will look strong by luck alone. A q below 0.05 means this link is unlikely to be one of those.

Pre-trial detainee share · % of prisonerslink with income -0.27 · independent
Redistribution · % reduction in the Ginilink with income +0.50 · moderate

“Link with income” is how closely each measure tracks GDP per person across countries, from −1 to +1.

Every country as a dot

Pre-trial detainee share · % of prisoners →Redistribution · % reduction in the Gini →8.21%73.5%2.67%48.3%Australia: 39.9% of prisoners, 27.7% reduction in the GiniAustria: 19.6% of prisoners, 41.4% reduction in the GiniBelgium: 23.6% of prisoners, 47.7% reduction in the GiniBulgaria: 8.79% of prisoners, 26% reduction in the GiniBrazil: 27.3% of prisoners, 13.8% reduction in the GiniCanada: 49.9% of prisoners, 29.3% reduction in the GiniSwitzerland: 51.9% of prisoners, 21.2% reduction in the GiniChile: 36.5% of prisoners, 8.68% reduction in the GiniCosta Rica: 23.7% of prisoners, 12.6% reduction in the GiniCzechia: 8.21% of prisoners, 43.5% reduction in the GiniGermany: 27% of prisoners, 38.7% reduction in the GiniDenmark: 23.9% of prisoners, 37.5% reduction in the GiniSpain: 17.7% of prisoners, 34.4% reduction in the GiniEstonia: 20.2% of prisoners, 33.5% reduction in the GiniFinland: 27.4% of prisoners, 47.2% reduction in the GiniFrance: 25.8% of prisoners, 42.2% reduction in the GiniGreece: 25.5% of prisoners, 36.9% reduction in the GiniCroatia: 42.4% of prisoners, 33.1% reduction in the GiniHungary: 20.7% of prisoners, 29.4% reduction in the GiniIndia: 73.5% of prisoners, 2.67% reduction in the GiniIreland: 19.3% of prisoners, 41.2% reduction in the GiniIceland: 42.6% of prisoners, 35.7% reduction in the GiniIsrael: 25.8% of prisoners, 23.2% reduction in the GiniItaly: 16.9% of prisoners, 36.2% reduction in the GiniJapan: 15.5% of prisoners, 34.1% reduction in the GiniKorea, Rep.: 35% of prisoners, 18.2% reduction in the GiniLithuania: 13% of prisoners, 29.7% reduction in the GiniLuxembourg: 48.3% of prisoners, 35.7% reduction in the GiniLatvia: 28.6% of prisoners, 28.1% reduction in the GiniMexico: 36.3% of prisoners, 3.77% reduction in the GiniNetherlands: 27.1% of prisoners, 34.2% reduction in the GiniNorway: 22.4% of prisoners, 39.5% reduction in the GiniNew Zealand: 42.3% of prisoners, 28.7% reduction in the GiniPoland: 10.9% of prisoners, 41.9% reduction in the GiniPortugal: 21.7% of prisoners, 36.5% reduction in the GiniRomania: 9.22% of prisoners, 38.1% reduction in the GiniRussian Federation: 15.4% of prisoners, 27% reduction in the GiniSlovak Republic: 13% of prisoners, 48.3% reduction in the GiniSlovenia: 39.8% of prisoners, 42.4% reduction in the GiniSweden: 27% of prisoners, 33.1% reduction in the GiniTurkiye: 14.4% of prisoners, 18.6% reduction in the GiniUnited States: 26.7% of prisoners, 22.1% reduction in the GiniSouth Africa: 38% of prisoners, 12.8% reduction in the GiniBGRCHECRICZEINDISLLUXMEXPOLSVKSVNTUR

best-fit line line after adjusting

Four ways to measure the link

MethodrpCountries
Standard (Pearson), not adjusted-0.4450.00343
By rank (Spearman), not adjusted-0.3750.01343
Standard (Pearson), adjusted for national income-0.4420.00343
By rank (Spearman), adjusted for national income-0.4980.00143

The rank version uses only each country’s place in line, from lowest to highest, so a few extreme countries count for less. The adjusted and unadjusted versions use the same 43 countries: those that report both measures and GDP per person. So the gap between them comes from the adjustment, not from a change in which countries are counted. Drop in the size of r after adjusting: +0.003 (a minus sign means it grew).

How solid is it?

Leaving out one country at a time, r ranges from -0.485 (without SVN) to -0.378 (without CHE). The bar above shows that range on a scale from −1 to +1, with the solid line at the full result. The single country that moves r most: CHE (+0.065).

Within each region

Countries are not separate, unrelated cases, and neighbors share a lot. A link that holds inside each region is far more believable than one that shows up only when comparing regions.

nr
Europe & Central Asia30-0.25

By income third

If the link shows up only in the richest third of countries, it is a feature of rich countries, not a general pattern.

nr
Poorest third15-0.17
Middle third14-0.28
Richest third14-0.59

By largest religious group

Countries grouped by a label they share, such as main religion, rather than by a number. Groups of fewer than twelve countries are not shown. These groups differ in income, region and history all at once. So a gap between them is a place to start asking questions, not an answer.

nr
Christians35-0.47

Without outliers (countries far outside the middle half of countries on either measure, by more than one and a half times the width of that middle half): r = -0.433 after dropping 2 countries.

Two series, one country

Both measures over the years for one country you pick. The two charts are stacked so they share only the years along the bottom.

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Over time, within countries

Everything above compares countries with each other at one moment. This section compares each country only with itself over 14years. So a link here can’t come from anything about a country that stays the same, such as its history, geography, institutions or culture.

Within countries over time, there is no link that is clearly more than chance (r = -0.018, comparing each country only with itself over the years, and each year only with the same year elsewhere). Whatever the cross-country picture shows, countries whose pre-trial detainee share moved did not tend to see their redistribution move with it.

Across countries (adjusted)-0.442for comparison
Within countries+0.011each country vs itself
…and vs the same year elsewhere-0.018q = 0.927 · 38 countries
Year-on-year changes-0.087q = 0.500
Read with care.
  • Almost all of this indicator's variation is between countries, not within them, so the within-country estimate rests on a small part of the data.

416 country-years (one country in one year), 38 countries, 2011–2024, about 11 years each on average. Share of the variation that happens within countries over time: 4% for Pre-trial detainee share, 12% for Redistribution. The margins of error allow for each country appearing many times, and for each year’s value being close to the year before.

Year-to-year changes are a cautious test, not a final answer. Looking only at changes from one year to the next removes each country’s own trends. But it also makes measurement mistakes louder, which pulls the results toward zero. A near-zero result here is weak evidence of no link, not proof.

With one measure years behind the other

0.30−0.3-60+10years Redistribution trails Pre-trial detainee share →lag -6: r = -0.122 (n = 230)lag -5: r = -0.162 (n = 265)lag -4: r = -0.176 (n = 309)lag -3: r = -0.156 (n = 343)lag -2: r = -0.130 (n = 381)lag -1: r = -0.086 (n = 404)lag +0: r = -0.018 (n = 416)lag +1: r = 0.030 (n = 415)lag +2: r = 0.003 (n = 415)lag +3: r = -0.083 (n = 416)lag +4: r = -0.172 (n = 413)lag +5: r = -0.224 (n = 413)lag +6: r = -0.231 (n = 410)lag +7: r = -0.267 (n = 408)lag +8: r = -0.265 (n = 409)lag +9: r = -0.212 (n = 380)lag +10: r = -0.156 (n = 352)

Same year (lag 0): -0.018. A peak away from zero does not show which comes first. These series change slowly — this year’s value is close to last year’s. That makes the curve smooth and nearly symmetric, whatever produced the data. Even a sharp peak at one lag (a gap of some years) would not prove that one measure changes the other.

The largest value on this curve (-0.27 at lag +7) is higher than the same-year one by 0.25. That gap is not a finding. It is the largest of 17 closely related estimates, and picking the biggest of many tests always makes it look bigger. That is exactly why nothing on this site is ranked or chosen by lag.

The data


% of prisoners
% reduction in the Gini		Years
India IND73.5%2.67%2023, 2011
Switzerland CHE51.9%21.2%2024, 2022
Canada CAN49.9%29.3%2023
Luxembourg LUX48.3%35.7%2024, 2023
Iceland ISL42.6%35.7%2024, 2019
Croatia HRV42.4%33.1%2024, 2023
New Zealand NZL42.3%28.7%2024, 2022
Australia AUS39.9%27.7%2024, 2020
Slovenia SVN39.8%42.4%2024, 2023
South Africa ZAF38%12.8%2024, 2017
Chile CHL36.5%8.68%2024, 2022
Mexico MEX36.3%3.77%2024, 2022
Korea, Rep. KOR35%18.2%2024, 2022
Latvia LVA28.6%28.1%2024, 2023
Finland FIN27.4%47.2%2024, 2023

United Nations Global SDG Indicators Database; series compiled by the International Labour Organization (8.3.1) and the UN Office on Drugs and Crime (16.3.2)
OECD databases as named on each indicator: PISA, Social Expenditure Database (SOCX), Income Distribution Database, Development Assistance Committee statistics, Family Database, Government at a Glance, Corporate Tax Statistics, employment and environment statistics

Sources

Pre-trial detainee share

Unsentenced detainees as a share of the prison population

United Nations Office on Drugs and Crime · via Our World in Data · CC BY 3.0 IGO · updated annual

Prisoners who have not been sentenced, as a share of everyone held. It measures how long justice takes, not how much crime there is. A country can imprison few people and hold most of them for years without trial. The site has no prison population rate, because the only series that compares countries is a private collection, not UN data.

Redistribution

Reduction in the Gini coefficient from taxes and transfers

OECD · via Our World in Data · CC BY 4.0 (OECD terms and conditions) · updated annual, except the snapshots noted per indicator · comparable from 2011 only

The Gini before taxes and payments minus the Gini after them, as a share of the first. It shows how much of the inequality produced by the market the government removes. It is built from the before-tax Gini above, so their pair is built from the same numbers and flagged. No "better" direction is set: a country may redistribute little because its market incomes are already equal.

How this was computed

Data used: most recent value in 2010-2025; values come from 2011–2024. To adjust for income, each measure is first predicted from GDP per person (in percentage terms, on a log scale) with a straight-line fit. Only what is left over is then compared. This is called a partial correlation. The line is drawn the standard way (ordinary least squares), which picks the line that comes closest to all the countries at once. The error margins allow for countries in the same region resembling each other, using 7 World Bank regions. The q-value corrects for testing all 12,497 pairs at once, using the Benjamini–Hochberg method. Underlying data last updated DYB 2024. How the country data works · explore Pre-trial detainee share and Redistribution

This page shows that two measures go together. It does not show that Pre-trial detainee share changes Redistribution, or the reverse. These figures also describe countries, not individual people. See the ecological fallacy.

More links with Pre-trial detainee share or Redistribution