Today, executions in China more often stoke anger than quell it. A 2007-2008 survey of nearly 4,500 people in three provinces funded by the European Commission found that only 58 percent supported the death penalty — compared with nearly 60 percent in the United States. Perhaps most revealing, respondents to the survey were aware of the death penalty’s uneven implementation. Sixty-nine percent believed, accurately, that poor offenders were more likely to be put to death than wealthy ones, while 60 percent thought that innocent people might be wrongfully convicted. Indeed, the Chinese press has been trumpeting wrongful convictions — such as that of a Henan Province man convicted of murder whose supposed victim turned up alive in 2010.

Other surveys suggest that support for the death penalty is higher among Chinese legal and political elites than the general public. Still, these groups have heeded calls from the people for change. Outcry over wrongful convictions has challenged the legitimacy of China’s judiciary at the very moment that the country has been trying to project an image of having a more modern and just legal system.

Interviews conducted by criminologists suggest that international criticism has had an impact as well. In 1977, a mere 16 countries had abolished the death penalty; today 140 countries — over two-thirds of the world’s nations — have done so in law or practice. Chinese legal scholars and judges are fully aware of their country’s role as the outlier.

In 2006 a group of reform-minded justices began formally advocating moderation in punishment. Led by Xiao Yang, then the Supreme People’s Court chief justice, they pushed the maxim “kill fewer, kill cautiously.” The following year, the high court began reviewing all capital cases, creating a strong disincentive for lower courts to hand out death sentences. The substitution in many cases of suspended death sentences — which in practice means offenders spend about 25 years in prison — was the result.

The shift met resistance from hard-liners who warned of a spike in crime. But pandemonium did not ensue. Some criminologists now argue that the harsh campaigns of the past in fact sparked violent crime, by making criminals reluctant to leave witnesses behind.

Chinese police continue to carry out punitive campaigns. But arrests made during such operations no longer automatically mean death. Even Chen Jun, a migrant worker convicted in a prominent 2008 case of stabbing the Canadian model Diana O’Brien more than 20 times, was given a suspended death sentence. The stabbing happened a mere month before the Beijing Olympics, as the police were cracking down on crimes big and small. Interviews I conducted over the past year with former police investigators, Mr. Chen’s family and Ms. O’Brien’s mother reveal that, in his case, the authorities were eager to show restraint. Instead of retributive justice, his trial suggested an emphasis on reparation and societal harmony.