This rule is simple: no killing. Batman`s refusal to take the lives of his enemies has been one of the character`s defining traits for decades, first evoked in „Batman“ #4 of the 1940s. In this story, which is involved in a sword fight with a gang of pirates, Batman tells Robin to „only use the abode of your sword“ because „we never kill with weapons of any kind.“ Batman co-creator Bob Kane bitterly recalled the creation of Batman`s no-kill code. In his autobiography Batman and Me, he wrote: „The whole moral climate changed between 1940 and 1941. You could no longer kill or shoot the bad guys. DC prepared its own comic code that every artist and writer had to follow. He was no longer the Dark Knight with all the censorship. But later, many fans and writers saw Batman`s refusal to kill in a different light. They argued that someone who had seen his parents shot in front of him would feel compelled never to stoop to the level of the criminals he fought by killing one of them, and would likely feel an aversion to guns. Because of this, even dark and dark depictions of Batman tend to show him that he adheres to his only rule. You see, the thing about the rule really only comes from the comics and is not well demonstrated in the movies.
Nolan`s Batman says he has only one rule, and orders Catwoman in TDKR „no guns, no murder“, but as I`m sure you know, he`s not too strict about this in the movies. For another explanation of the different iterations of movies (with the exception of Schumacher, because I couldn`t deal with them): Apart from the Batman „Earth One/New Earth/Prime-Earth,“ many different versions have established themselves that have similar rules and codes of conduct. In Joel Schumacher, Batman seems to follow the rules against killing criminals. In dialogue with Dick Grayson, he hints that he adopted him to prevent him from falling down a darker path. Batman also stops using weapons that can be used in lethal ways, including those equipped for his vehicles. Any normal person in his position would kill, even Superman is willing to do it, but not Batman because he is no longer normal and this speaks to the difficulty of a Gotham city. Batman is as crazy as everyone else deep down, he happens to be on our side. That`s why I like the rule, because if you take it, then he`s a normal person that Batman hates and is exhausted by his enemies, but he still wants to reform it to the core. For this reason, according to this fan theory on Reddit, it has a different rule and no murder. This rule is not to call your antagonist by his chosen thug name, but by his real name.
As much as I personally would have little trouble killing Batman, as long as it wasn`t too outrageous. The fact is that the rule pretty accurately defines the character of Batman – a Batman who has no qualms about killing is just another anti-hero. This removes the emotional investment of the character and turns him into a character. Batman fans usually know that the only thing that distinguishes The Dark Knight Vigilante from the villains he fights is his „only rule“ that Batman won`t kill his enemies. This rule has been the subject of controversy among many fans, writers and even filmmakers, blurring the lines between murder and the famous „one rule“. The latest case of controversy came when Zack Snyder`s Batman vs. Superman divided fans and critics alike about the DC movie. Snyder`s version of Batman, at least in this movie, was a Bruce Wayne who hated, grew old and regretted and had no respect for the lives of his enemies. When fans began complaining about Batfleck`s murderous techniques, Snyder responded by claiming that „fans live in a dream world“ when they refuse to believe Batman shouldn`t kill.
Throwing the term „dream world“ into a superhero universe is certainly debatable; However, Snyder has historical precedent to support his argument. Fans would be ignorant to deny that Batman never killed. In fact, Batman killed in his very first comic book issue. In the Batman: Arkham video games, his version of Batman adheres to the same rules as regular continuity, such as not killing or using guns. He also refuses to do so on several occasions, including with Joker in Batman: Arkham Asylum and Ra`s al Ghul in Batman: Arkham City, and even tries to save her. Batman`s non-lethal tactics are also mentioned by henchmen, including the Arkham Knight`s army. However, he probably murders some characters and henchmen throughout the series. Officially, Batman`s „No Killing“ rule went into effect in Batman #4.
During a sword fight with pirates, Batman tells Robin, „Just use the abode of your sword, Robin! Remember, we never kill with weapons of any kind! In addition, the character began working with the Gotham City Police Department and was portrayed as a law enforcement officer.[1] This now meant that Batman was no longer considered a vigilante and had to work within the guidelines of the law. The Batman & Dracula trilogy is probably exactly what you think: a three-part story told in the 90s where an Elseworlds version of Batman learns that Count Dracula has come to Gotham City. While this arc is by no means part of the main DC Universe, it is nonetheless notable because it contains some of the Dark Knight`s most brutal killings. Batman`s code is crucial to the development of his character, whether applied and used as his weakness or ignored and shows that he has passed his breaking point. Many filmmakers have taken the helm of the Batman universe and everyone has used Batman`s code as a character development tool.