Out of the numerous characters that have been Robin not all of them have followed the “no killing” rule of the Batman. The idea of a Robin killing people may sound strange, not keeping up with strongest beliefs of Batman but here we list down 4 times Robins have had blood on their hands.
Tim Drake Kills Joker
The Joker kidnaps Tim Drake and makes him into believing that he is his son, invites Batman over to show how he actually killed Tim Drake’s identity and make him Joker Junior, by brainwashing his memories. He has beaten Batman and can kill him, but in order to have fun, he orders Tim to kill Batman who eventually kills him instead, scarred by all this, he himself turns into Joker when older.
Red Hood Kills Joker
Joker finished Jason Todd or so he thought, Todd came back from Lazarus pit and was after joker’s life since then but Wayne never allowed him to follow this path. Later while Jason travelled the multiverse he discovered that the Batman of earth-51 had resorted to the use of lethal force and killing but in the succeeding battle to escape the dying world, Bruce was murdered. While mourning, an alternate Joker invites trouble by mocking Jason, he then killed that Joker forever by devastating his skull with a rock before he left earth-51.
Todd Kills His Teachers And The Untitled
After the retcon in the New 52, when Todd is shown to have been revived by Ra’s with the help of the Lazarus pit, he is trained at the All castle, of which he’s later made the guardian of. After Jason figured out that the All-Castle’s people were dead, which was told to be the doing of The Untitled and figured that the bodies attacking him were the reanimated versions of his teachers, who attacked him, Roy and Starfire, Todd had to kill the. Later in the story too, Todd kills the members of the untitled.