The Chinese courts seem to be using rules of thumb: the most egregious offenders get the most severe punishment, and the scale slides down. This has a surface appearance of fairness. Defense attorneys in capital cases will doubtless recognize the futility of a direct assault and will have to focus on the arbitrariness of the imposition of death sentences. For example - in the SanLu cases "substantial certainty" that someone will die sufficed. In the Xinjiang cases some killers were executed and others spared.
The guidelines issued by the Supreme People's Court in drug cases make distinctions based on quantity, whether children were involved, etc. But looking across the range a coherent pattern does not emerge: some who personally killed are spared; others who risked grave or fatal harm to others are not. Such divisions may be ground which Chinese capital defense lawyers can till. - GWC