Among the tasks that Suming had assigned to Zhang Siming, the last two were to investigate Zhou Jing and Chen Yuan's social relations to see if either of them had ever made enemies and to look into the background of the driver involved in the incident.
Specialization is key in any trade, and investigating people was not Zhang Siming's strong suit, especially out of town, where the well-known lawyer had little advantage to speak of. Following Suming's instructions, Zhang Siming promptly hired a local private detective agency at a high price to handle these two matters.
Results for both tasks came quickly.
In life, it's impossible not to offend anyone; Zhou Jing and Chen Yuan liked to mingle in society, making it easy to find past conflicts with others.
However, these disputes were mostly about mutual dislikes, verbal altercations, and at worst business conflicts or physical fights, but nothing serious enough to warrant hiring someone to commit murder.