Killing is intentionally causing the death of any other living creature, and it has a highly controversial position in the DC Universe. The superhero community has to deal with it as a moral, legal and political issue in crime fighting. Lethal force used against super-villains and other criminals is usually met with negative public opinion, as heroes working outside the law can't be held up to the same standards as regular members of law enforcement. The psychological effects and the philosophical implications of ending another person's life make this a line that most heroes choose never to cross.
Heroes who regularly kill or have lost their killing virginity:
- Arsenal killed the Electrocutioner for his role in Lian Harper's death.
- Antaeus murdered the leader of a middle eastern country. 
- Atom Smasher
- Batgirl (Cassandra Cain) was trained from an early age by the assassin David Cain, and committed her first murder at a very young age. This completely traumatized her.
- Batman was forced to shoot Darkseid in the chest with a Radion bullet to save existence itself during Final Crisis.
- Black Adam
- Black Canary was forced to kill Everyman while he posed as Green Arrow on her wedding night. 
- Black Lightning murdered corrupt corporate executive Martin Somers to avenge the death of his niece Joanna Pierce.
- Black Thorn
- Captain Atom
- Captain Boomerang, Jr.
- Catwoman killed Black Mask after he brutally tortured Maggie and killed Simon Burton.
- Chief Justice Max
- Crimson Avenger
- Damian Wayne
- The Elite
- Enchantress killed the Pentacle member White Rabbit.
- Faust relit the fires of Hell by killing the Enchantress.
- Fire murdered villain Colonel Computron.
- The Flash killed Professor Zoom to protect his fiance Fiona Webb after Zoom killed his first wife.
- Ghost Fox Killer
- Green Arrow struggles with the lethal force conflict significantly more than most others. His first kill was a sniper he accidentally shot fatally when his arm slipped at a crucial moment. The next was a man in the middle of torturing his girlfriend Black Canary who intended to rape and murder her. The Cross Roads storyline where he began to doubt his motivations and acted more as an antihero saw him kill 14 criminals during his adventures, although it is implied there were more. Cry for Justice had him murder Prometheus in cold blood after the super-villain murdered thousands of Star City inhabitants with a massive terrorist plot.
- Green Lantern Corps
- Guy Gardner generally avoids killing, but he took out Sinestro Corps member Duel Eknham with a shot through the head when he was really freaking pissed.
- Hal Jordan
- Hannu relies more on his own strength than his Ring, and killed his Sinestro Corps counterpart Horku by punching straight through him.
- Jack T. Chance
- John Stewart
- Human Bomb killed the supervillain, Doctor Polaris, after witnessing the Freedom Fighters slaughter.
- Jason Todd
- Jonah Hex
- King Faraday
- Nightwing once beat the Joker to death with his bare hands during Last Laugh, believing him to be responsible for the death of Robin. Robin was not actually dead, and Batman revived the Joker so Nightwing wouldn't have blood on his hands.
- Obsidian killed his abusive, adoptive father James Rice. 
- Omega Men
- Sonny Sumo killed mercenary Megayakuza. 
- Star Boy
- Superman executed three Kryptonian prisoners using Green Kryptonite, General Zod, Quex-Ul and Faora of the Pocket Universe. They had committed global genocide by murdering every single human on Earth in their reality, and swore that they would do the same again if they ever escaped.
- Tawky Tawny killed Kalibak during battle. 
- Ultramarine Corps
- Wild Dog
- Wonder Woman snapped Maxwell Lord's neck during Sacrifice to prevent him from taking over the planet with a mind-controlled Superman.
- No special notes.
- No trivia.
Links and References
- ↑ Justice League: The Rise of Arsenal #4
- ↑ JLA: Superpower
- ↑ Detective Comics #734, see excerpt
- ↑ Final Crisis #6, see excerpt
- ↑ Green Arrow and Black Canary Wedding Special #1
- ↑ Green Arrow (Volume 3) #31
- ↑ Shadowpact #3
- ↑ Day of Judgement #4
- ↑ Checkmate (Volume 2) #11
- ↑ Flash (Volume 1) #324, see excerpt
- ↑ Flash (Volume 1) #217, see excerpt
- ↑ Green Arrow: The Longbow Hunters #2
- ↑ Green Arrow (Volume 2) #84-90
- ↑ Justice League: Cry for Justice #7, see excerpt
- ↑ Green Lantern Corps (Volume 2) #26, see excerpt
- ↑ Green Lantern (Volume 4) #24, see excerpt
- ↑ Infinite Crisis #1
- ↑ Joker: Last Laugh #6
- ↑ JSA #9
- ↑ Final Crisis #2
- ↑ Starman (Volume 2) #3
- ↑ Starman (Volume 2) #60
- ↑ Superman (Volume 2) #22, see excerpt
- ↑ Final Crisis #6
- ↑ Wonder Woman (Volume 2) #219, see excerpt