Global Covid-19 lockdown restrictions have led to a sharp decline in violence and stealing as criminals and potential victims were forced to stay at home, an international study says.
Robberies and thefts reduced by nearly half in the 27 cities examined.
But the study did not include fraud and online scams, which have surged during the pandemic, as victims spend more time in front of their computers and criminals modify their techniques.
The research, which spanned 23 countries in the Middle East, the Americas, Europe and Asia, analysed statistics for six types of crime recorded by police: assault, theft, burglary, robbery, vehicle theft and homicide.
The study examined the short-term effects of the first lockdown in the surveyed countries and found, on average, that these crimes were down by 37 per cent.
Murders were largely limited to three cities – Cali, Lima and Rio de Janeiro – and were down, but not by as much as other crimes examined in the study published by Nature Human Behaviour.
Researchers attributed the 14 per cent decrease to the fact many killings take place in the home, so the effect of stay-at-home orders was negligible.
Organised crime gangs – regarded as being responsible for a significant proportion of killings – were also less likely to change their behaviour in accordance with lockdown rules compared with law-abiding citizens, researchers said.
The data showed changes in criminal behaviour after the World Health Organisation in March last year declared Covid-19 to be a public health emergency of global concern.
Countries responded with a range of measures to limit infection, including travel bans, stay-at-home orders and restrictions on public gatherings.
At the peak of the global lockdown in March and April last year, daily movements for shopping and leisure decreased by more than 80 per cent in many countries in Europe and Latin America.
The restrictions led to remarkable declines in crime in areas such as Barcelona, Spain, where thefts fell to a tenth of the pre-pandemic levels of 385 a day.
The smallest decrease in crime was in the Swedish cities of Malmo and Stockholm, where authorities tried to combat Covid-19 with a limited lockdown. The largest decline in offending – about 80 per cent – was in Peru's capital Lima. Peru was one of the early adopters of lockdown, just 10 days after its first reported case.
Across all the cities studied, the average reductions for robbery and theft were 46 and 47 per cent respectively, with burglaries down 28 per cent.
The largest decreases were in once-thriving but now sparsely populated public spaces because fewer potential victims spent time in crime hotspots, said the study.
Lead author Dr Amy Nivette, of Utrecht University in the Netherlands, said: "In cities with more stringent stay at home orders, we saw larger declines in street crimes compared to cities with fewer constraints on public life. However, the declines were relatively short-lived."
