A driver dies in the Sichuan city of Luzhou while police are trying to get him to move his truck, which they say is illegally parked. The body is noticed by passers-by and word quickly spreads that the 58-year-old man was beaten to death. A crowd gathers and its anger gets out of control. Soon, thousands of people are reportedly rampaging through the streets, throwing bottles and stones and upturning and torching police vehicles. It is a story that we would probably not be aware of were it not for the pervasiveness of social media on the mainland. Within minutes last Wednesday, microblogs were abuzz with purported details and photographs. In the days before the internet and mobile phones, police would in all likelihood have covered up the incident and it would not have been reported. Now, with scrutiny all around, they have to be transparent. At a press conference on Thursday, police gave their account of what had happened. They said the man had become agitated while they were talking to him, taken medicine he had in his vehicle and died shortly after. Widespread corruption means that the honesty and integrity of officials is often questioned on the mainland. It is one of the reasons there are upwards of 100,000 annual "mass incidents", the official term for unrest, protests and riots. Sadly, the rapid escalation of this incident is testament to the level of social discontent and of distrust in government. With two versions of events circulating and so much anger, authorities would do well to ensure that the investigation they have promised is carried out properly and does its best to find the truth. In the absence of a free press, social media has created what amounts to citizen journalism. Citizens rightly seek honesty from the people who govern them and maintain law and order. It is in the interests of the authorities that they strive to comply by being open and transparent. But that is only part of what is needed. There also has to be a media that is able to scrutinise all aspects of government and report freely.