Three Chinese students attending a high school in southern California will serve time behind bars for kidnapping and assaulting a female classmate in a high-profile bullying case.

Zhai Yunyao, Yang Yuhan and Zhang Xinlei reached a plea deal with prosecutors on Jan 5. The three 19-year-olds pleaded no contest to criminal charges of kidnapping and assault. Zhai, the prime culprit, faces 13 years in prison, Yang 10 years and Zhang 6 years, according to a report in The Los Angeles Times. And they will be deported to China after serving their sentences.

The bullying case, which came to light in March 2014, has caused quite a stir in China. The case, the media speculated, involved a dispute over a love affair and the target of the three students, who sought the help of some other teenagers, was an 18-year-old female classmate surnamed Liu. The victim testified that she was taken to a park, stripped, kicked, slapped and burned with cigarettes. Her ordeal, she said, lasted more than five hours.

The plea deal was "the best resolution" as there is "too much of a risk to go to trial", the attorney of one of the defendants was quoted as saying by the Associated Press. And prosecutors agreed to drop the torture charge under the plea deal.

The three students were "deeply shocked" after learning that what they assumed to be a "prank" was actually a felony in the United States which could lead to a life sentence, according to media reports. Judging from their reaction, the three thought the maximum punishment they would get was demerit points from their school. Worse, a parent of one of the students was also detained for trying to bribe prosecutors into dropping the case.

The California case shows how ignorant Chinese students and parents are about US laws, but it also serves as a reference for similar cases in China. Bullying incidents are not rare in China's schools. Bullying cases have hit the headlines from time to time; sometimes perpetrators have even uploaded videos of their misdeeds on the Internet.

However, few offenders receive proper punishment in China. In most of the cases that do not involve severe physical harm, the only "punishment" offenders receive is criticism from schools. As for parents, most of them consider bullying incidents as "small fights" between their children, and it is precisely because of such an attitude that bullying cases have not declined in China.

Moral education is important, but a special law to deal with bullying cases would be more effective. For example, led by the US Department of Education, a Bullying Prevention Steering Committee consisting of many other federal departments is in place to guide efforts to end bullying in US schools. In fact, 46 of the 50 US states now have their own anti-bullying laws.

Perhaps China could learn from the US in this regard, and the National People's Congress, the country's top legislature, along with the Ministry of Education, could enact a specific anti-bullying law.

An important lesson to learn from the California bullying case is "joint liability". Zhang Xinlei, who claimed to be a bystander during the entire incident, has also received severe punishment. Bullying is often a group action, and without accomplices like Zhang, incidents like the one in California might not take place. So despite not being the prime culprit, Zhang bears joint liability and should receive befitting punishment.

Another point to be noted is that though most of the bullying cases involve minors, who are usually immune to criminal responsibility, judges in the US have the right to treat them as adults if the crimes are severe or if they have criminal records.

Physical wounds can heal with time, but mental trauma can continue causing pain for the rest of a bullying victim's life. This is something lawmakers ought to keep in mind while drafting legislation on bullying.

The author is an editor at China Daily. lifangchao@chinadaily.com.cn