Crime is more common in Indian cities where nighttime satellite maps show bright pockets of wealth standing out amid poorer, dimmer neighbourhoods, with even small rises in inequality tied to more offences.
Researchers at IIT Kharagpur have found that a 1 per cent rise in economic inequality — assessed through nighttime artificial lights — is linked to a 0.5 per cent increase in crime rates.
While earlier global research has linked economic inequality to higher crime,
the new study provides the first evidence of similar patterns in data pooled from 49 Indian cities.
“Economic inequality appears to create conditions where crime is more likely,” said Siddhartha Chattopadhyay, an economist and associate professor at IIT Kharagpur’s humanities and social sciences department, who supervised the study. “Our results bolster evidence for the idea that crime isn’t driven only by individual choices but is shaped by the socio-economic backdrop where it occurs,” he told The Telegraph.
Chattopadhyay and his colleagues analysed statistics from the National Crime Records Bureau (NCRB) alongside satellite maps of nighttime lighting, a reliable proxy for economic activity as shown by other researchers.
The NCRB data show that Delhi is the nation’s crime capital, with 1,500 crimes per 100,000 population during 2016-21, followed by Kollam (922), Thiruvananthapuram (892), Bhopal (859) and Gwalior (837).
In contrast, Calcutta ranked among the nation’s safest cities, with just 127 crimes per 100,000 population during 2016-21, sandwiched between Kannur (111) and Malappuram (121) and ahead of Coimbatore (198) and Hyderabad (203).
“We pooled data from 49 cities — future city-specific studies could explore how economic inequality, among other factors, contributes to high and low crime rates in these cities,” said Christopher Mathen, the study’s lead author, now pursuing post-doctoral research at the Indira Gandhi Institute of Development Research, Mumbai.
Four years ago, scientists at Wageningen University in the Netherlands demonstrated that nighttime lights highlight global hotspots of economic inequality. High-income countries are generally less unequal than low-income ones, with pronounced disparities in China, Southeast Asia, Africa and South America.
At the city level, data on economic inequality are scarce, Chattopadhyay said. “We’ve therefore used differences in nighttime lighting across urban India as a proxy.”
The study, published in the research journal PLoS One, is part of a broader effort to explore how economic and institutional factors influence crime across cities and states.
Using data from 23 Indian states between 2001 and 2021, the researchers also found that higher conviction rates are linked to lower crime, including attempted murder, deaths by negligence, kidnapping, counterfeiting and cheating. A one per cent increase in the total conviction rate in the previous year corresponded to about a 0.3 per cent drop in total crime.
“We’ve generated fresh statistical evidence that increasing conviction rates serve as a deterrent to certain crimes,” said Mathen.
Historical research supports these patterns, with subtle distinctions. A 1968 study by University of Chicago economist Gary Becker had suggested that crimes of passion, such as murder, are less responsive to deterrents than planned offences. Police strength also has a nuanced effect.