The original explanation of legitimate defense:

The constituent elements of legitimate defense include the legitimacy of the defense intention, the urgency of the defense behavior, the legality of the defense object, and the appropriateness of the defense limit. The legitimacy of defensive intentions means that defensive actions must be for the legitimate purpose of protecting legitimate rights and interests, and must be directed at the illegal intruder and his illegal infringement behavior. The urgency of defensive actions requires that the defensive actions be carried out while the unlawful infringement is ongoing. The legality of the defense object means that defense actions can only be directed against the illegal intruder and his illegal infringement behavior, but not against unrelated persons or illegal interests. The appropriateness of the defense limit means that the defense behavior cannot obviously exceed the necessary limit, otherwise it may constitute excessive defense. Although there is no criminal liability in this case, the punishment should be reduced or exempted.

When judging whether the party that strikes first in a fight between two parties bears responsibility, multiple factors need to be considered:

1. Whether both parties are at fault. If the fight is caused by a civil dispute, then both parties should bear corresponding civil liability for compensation based on their respective faults. Generally, the party who strikes first is more responsible for the fault.

2. Whether there is insult or defamation. If the other party commits insulting or defamatory behavior, and the circumstances are egregious, liability may be different.

3. The severity of the injury. If a fight results in serious injury to one of the parties, there may be criminal liability, such as intentional injury.

4. Whether there is legitimate defense. If the person being hit acted in self-defense, they will not be held legally responsible.

To sum up, as long as certain conditions are met, legitimate defense can be carried out for illegal intrusion into other people's homes, illegal detention and deprivation of personal freedom. The objects of unlawful infringement should not be artificially restricted, thus limiting the scope of legitimate defense.

Legal basis:

"Criminal Law of the People's Republic of China"

Article 20

In order to make the country and the public If the interests, personal, property and other rights of oneself or others are protected from ongoing illegal infringement, and actions taken to stop the illegal infringement and cause damage to the illegal intruder, it shall be deemed as legitimate defense and shall not bear criminal responsibility.