Thirty criminal cases and more than 300 misdemeanor cases have been resolved with the help of micro blogs since becoming the subjects of investigations by public security authorities one year ago in South China's Guangdong province, a senior local police officer said.
The cases concerned crimes such as intentional injury, robbery, theft and fraud, rape, and child trafficking, said Liu Bo, head of the network operation department under the Guangdong provincial public security department.
Since March 2010, when police in Zhaoqing city started the first official police micro blog in Guangdong, 72 police micro blogs have been opened on sina.com, qq.com and the department's official website, gdga.gov.cn.
"In the beginning, we had tried to use new media to release public security information to interact and communicate with the public," Liu said, adding that they didn't project the likely results of their decision.
Those grew to conspicuous dimensions by late February, about a year after the micro blogs had been started. By then, the sites had attracted more than 1 million postings of messages and comments and more than 170,000 fans, according to the department's statistics.
Most of the messages left by netizens asked for advice about various laws and regulations; a small number sought help or provided clues. And a mere handful reported violations of discipline by police officers.
"They thought that it's a direct, convenient and quick way to communicate with us," Liu said.
The police, meanwhile, try to make timely releases of information that pertain to case developments and crime tips. They also use the blogs to refute rumors, he said.
According to Liu, the police receive more than 1,400 messages on the micro blogs a day. After sorting them out, they make some 400 to 500 responses, from which have resulted about 100 clues pertaining to criminal crimes.
"After receiving the crime reports and after a preliminary identification and verification, we reported the clues to the relevant departments, including the criminal investigation, economic investigation, public order and drug enforcement departments," he said.
"The relevant department will then follow up on the clues and begin to investigate the cases," Liu added. "And they will respond to informants soon and keep in regular touch with them."
On May 13, 2010, a netizen, who goes by the name Army Brother, claimed on a police micro blog that a large number of detonators and explosives were hidden in a shop near a kindergarten in the Baiyun district of Guangzhou, the provincial capital.
After noticing the report, the blog's operator relayed the information to the Guangzhou police, who rushed to the scene and discovered 5,400 electrical detonators, 31.2 kilograms of explosives and 150 meter of fuse in the shop. As it turned out, the bomb paraphernalia had been stored there by a hydropower engineering company.
Liu said even though micro blogs have played an important role in solving crimes, they are not useful in all circumstances.
"If you were in bad need of help, or witnessed a crime, please make a report by dialing 110," he said.
"And if you want to make a report that includes photos or tape or video recordings, please get in touch with us directly by e-mail or by writing a letter, instead of writing on a micro blog. That will help to protect the privacy of the parties involved."
"Micro blogs have disadvantages as well," said Wu Ming'an, a law professor at China University of Political Science and Law.
"They might allow for invasions of privacy or provide a means of spreading fake information or even slander."
