Zhang Yimou's movie "Article 20" mainly talks about three cases, if you talk about the severity of the case, Wang Yongqiang's case undoubtedly attracts the audience's attention more, followed by Zhang Guisheng's case. 
The severity of Han Yuchen's stop to school bullying cannot be compared with the other two cases, this case is administrative detention at best, and it can be solved with an apology at worst. In addition, there are a lot of comedy scenes around Han Yuchen's failure to apologize, and the audience is laughing in the cinema, and the tragic Wang Yongqiang case is like something happening in two worlds. So why did Zhang Yimou spend a lot of time and scenes describing this incident? 
1. The dilemma behind school bullying Han Yuchen and Zhang Ke are both students in the No. 3 Middle School of the local key school, of which Han Yuchen is a borrowed student. Zhang Ke gathered several classmates to bully another classmate on campus, and Han Yuchen took the initiative to protect the weak, and as a result, Zhang Ke's nose was broken. This incident has become the cause of a series of incidents, in principle, the nature of this matter is obvious, Han Yuchen is righteous and courageous, Zhang Ke is the leader of campus bullying, it seems that the problem is easy to handle. 
However, because many classmates, including victims of campus bullying, did not dare to offend Zhang Ke, no one stood up for Han Yuchen as a witness, so Han Yuchen, who injured Zhang Ke, fell into a passive situation, and if there were no witnesses and evidence, his behavior of injuring his classmates would be seriously dealt with and could be administratively detained and expelled. Han Yuchen's predicament is actually one of the reasons for the recurrence of school bullying, some bullying students like Zhang Ke are always fearless, and victims and ordinary classmates often choose to remain silent because they are afraid of things or trouble. 
Interestingly, Han Yuchen's predicament seems to be easy to solve, according to Zhang Ke's father's request, he only needs to apologize to Zhang Ke in person to write it off, why? Quite simply, the power behind students like Han Yuchen and Zhang Ke began to move. 
Second, the power behind the students Some viewers think that the plot of "Article 20" is unreasonable, even if Han Yuchen is a borrowed student, his father Han Ming is also a local prosecutor, even if Han Ming is only suspended, this kind of family is not something that a teaching director can afford. You need to look at this matter from three aspects, first, the teaching director of the key middle school is also a well-known figure in the local area, in principle, it is really difficult to say who is higher and lower in social status between him and Han Ming, and as long as the teaching director is clean, he will not be afraid of a prosecutor like ordinary people. Second, before Zhang Ke's campus bullying was not verified, the teaching director and his son Zhang Ke were the ones who temporarily took over, and it was Han Ming and his family who wanted Director Zhang's father and son. Third, there is another very critical issue, the reason why Director Zhang only asked Han Yuchen to apologize was that in addition to being a little weak about his son, I am afraid that he also had something to do with Han Ming's identity as a prosecutor, and he didn't dare to make a big deal too much, so when he saw Han Ming and Li Maojuan again and again, he only asked for a verbal apology, saving enough face. 
Han Ming, as a father, must know his son, but as a prosecutor, he also understands that before the campus bullying is confirmed, Han Yuchen is in a very passive position and has to bow his head temporarily. Therefore, in the first round of Han Yuchen and Zhang Ke, Director Zhang and Han Ming formed a temporary unstable balance, and there are three ways to break this balance, one is to find out the truth about campus bullying and return Han Yuchen's innocence. Second, Han Yuchen officially apologized to Zhang Ke. Third, there is an imbalance of power or interests. In this case, it is no longer necessary for Han Ming to send an iron cover Moutai to Director Zhang, except that it will make Han Ming make mistakes and lose face, it is difficult to break this balance, after all, Director Zhang is not short of those two bottles of wine. 
At this time, Li Maojuan's brother Li Maoquan appeared, he is the deputy captain of the criminal police team, although this identity has no direct effect on Director Zhang of the key middle school, but he can exert influence on the police station in the jurisdiction of the third middle school, if the police station rejects Director Zhang's appeal, then Han Yuchen does not have to apologize. However, Li Maoquan failed, he said that the "note" had already been handed over, that is, the case filing documents had been reported, and there was no way to withdraw it, so he could only do business. So, did Li Maoquan "exert force" on his nephew behind his back? This is actually a problem, maybe he just went to the police station to look at the documents from a professional point of view, and when he found out that Director Zhang was indeed temporarily in charge, he decided not to participate anymore. 
As a result, there was a situation in "Article 20" that made it difficult for realistic audiences to agree, a deputy captain of the criminal police team and a prosecutor were helpless to be the director of high school. In fact, we should understand it this way, the reason why Director Zhang is not afraid of the two public prosecutors and law comrades is that in addition to his temporary possession, it is estimated that he has nothing unclean and is not afraid of investigation. His son is his son, he is him, and it cannot be mixed up. The reason why Han Ming and Li Maoquan became so "cowardly" is actually a manifestation of their compliance with the law as law enforcers, and Han Yuchen's current situation is either an apology or a business affair. Power does not play a wrongful role through wrongful acts at this time, which is the spirit of the rule of law upheld by Article 20. 
3. The final official businessJust when Han Yuchen's situation became more and more disadvantaged, another person who broke the balance appeared, Director Zhang's nephew, Lawyer Chen. Lawyer Chen understands the law and will also take advantage of legal loopholes, he is very willing to help Han Ming, but he will not make any demands, this is a manifestation of high emotional intelligence, he wants to use Director Zhang's family affection to transform the family affection into his connections with prosecutor Han Ming and Li Maoquan, the deputy captain of the criminal police team, and let Han Ming and Li Maoquan owe him a favor after settling his uncle. It is not uncommon for a person like Mr. Chen to do something illegal, but he will take advantage of the edge and loopholes of the law to do some unspoken things. 
Just when Lawyer Chen was about to succeed, Zhang Ke found a thug to beat Han Yuchen, and Li Maojuan, who had been swallowing her anger before, finally turned her face, This time she and her husband and son finally reached an agreement not to apologize, just to the end. However, Li Maojuan's husband and brother are both in the public security and legal system, but Li Maojuan herself is a little impulsive, she lost her mind in the fight with Director Zhang, and the two caused Director Zhang to fracture during physical contact. The campus bullying case was confirmed, Han Yuchen was fine, and justice was proclaimed, but Li Maojuan had to be administratively detained again.
Although the scene of Li Maojuan "going in" is very funny, behind the laughter, we also have to think about why Zhang Yimou had to let Li Maojuan be detained instead of letting her use her connections or favors to escape punishment. In fact, this is the difference between Han Yuchen's case and Wang Yongqiang's case. Wang Yongqiang's case requires that the investigators cannot judge the nature of the case in full accordance with the standards of rational people, and must consider that Wang Yongqiang and his wife are living people, and they cannot be harshly criticized for maintaining rational minds and behaviors when their lives and dignity are brutally trampled on.
Han Yuchen's case is the opposite, he can't lose his principles and apologize to the bad guys because he can't find evidence for the time being, nor can he bow his head and admit his mistakes to the abuser because the director of academic affairs may lose his borrowing qualifications, let alone use his power to settle the matter in private because his father is a prosecutor and his uncle is the captain of the criminal police. Han Yuchen's case must be handled officially, whose fault is whose fault is whose fault, Han Yuchen who stopped school bullying and protected his classmates should be praised, and Li Maojuan, who caused the other party's parents to break their bones due to quarrels and tears, should be detained. We should be grateful to Zhang Yimou, he did not deliberately pursue the so-called happy ending and let Li Maojuan escape punishment, this case, like the Wang Yongqiang case and Zhang Guisheng case, embodies the precious spirit of the rule of law.