Four PRC Bus Drivers Arrested And Charged For Instigated Other SMRT Drivers To Go On Strike

Killing The Chicken To Frighten Monkeys - 杀鸡儆猴

Question: Why others who participated are not charged too? Does the law states that only the ringleaders are liable to be charged for illegal strike?

Yahoo! News Singapore, 29 Nov 2012

Four China nationals were charged Thursday evening for engaging in a conspiracy to get SMRT bus drivers to take part in an illegal strike earlier this week.
Those charged -- He Jun Ling, 32; Gao Yue Qiang, 32; Weng Xianjie, 39; and Liu Xiangying, 33 -- had been arrested by police over Wednesday and Thursday.
Seen as the ringleaders, Gao, Weng and Liu each face one count while He faces two counts of inciting SMRT workmen to take part in the strike.
According to the charge sheets, He made a post in the Chinese language on http://tieba.baidu.com titled "The insults and humiliations suffered by Singapore drivers (SMRT) (where is the dignity of the People's Republic of China bus drivers)" Full story

Related:
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  2. Police arrest four Chinese drivers for Singapore strike - MSN Malaysia News
  3. Police arrest four Chinese drivers for S'pore strike - thesundaily.my 
  4. Four Chinese drivers charged over Singapore bus strike - Malaysia Star 
  5. Singapore charges organizers of rare strike - boston.com 
  6. Singapore charges Chinese immigrant bus drivers who instigated first strike in nearly 30 years - The Washington Post 
  7. Singapore charges organizers of rare strike - BusinessWeek 
  8. Singapore charges organizers of rare strike - FindLaw.com 
  9. Singapore charges Chinese immigrant bus drivers who instigated first strike in nearly 30 years - The Republic