The bad guy killed someone else, and I helped kill the bad guy from behind. Should I bear legal responsibility?

The key is to see if your behavior has exceeded the necessary limit, and self-defense cannot obviously exceed the necessary limit, causing great damage; If it does not exceed, then it will not bear criminal responsibility. If it is exceeded, it is an excessive defense and it is necessary to bear corresponding responsibilities.

Self-defense (also called self-defense) is a concept in the criminal law of continental law system. In order to protect the state, public interests, personal, property and other rights of oneself or others from ongoing illegal infringement, stopping illegal infringement and causing damage to the illegal infringer, it belongs to self-defense and does not bear criminal responsibility. If justifiable defense obviously exceeds the necessary limit and causes great damage, criminal responsibility shall be borne, but the punishment shall be mitigated or exempted. Taking defensive actions against violent crimes such as assault, murder, robbery, rape, kidnapping, etc., which seriously endanger personal safety, and causing casualties of illegal infringers, is not excessive defense and does not bear criminal responsibility. It, emergency avoidance and self-help behavior are all ways of right self-help.

Article 20 of the Criminal Law stipulates: "In order to protect the state, public interests, personal, property and other rights of oneself or others from ongoing unlawful infringement, stopping unlawful infringement and causing damage to the unlawful infringer, it belongs to self-defense and does not bear criminal responsibility."

If justifiable defense obviously exceeds the necessary limit and causes great damage, criminal responsibility shall be borne, but the punishment shall be mitigated or exempted.

Taking defensive actions against violent crimes such as assault, murder, robbery, rape, kidnapping, etc., which seriously endanger personal safety, and causing casualties of illegal infringers, is not excessive defense and does not bear criminal responsibility.

It should meet four conditions:

1, legitimate defense must be aimed at illegal infringement;

2. It must be that the illegal infringement is in progress;

3. Self-defense must be aimed at illegal infringers;

4. Self-defense cannot exceed a certain limit.