As a Death Trope, all spoilers will be unmarked ahead. Beware.
Murder by Inaction in Western Animation.
- Avatar: The Last Airbender:
- In "The Siege of the North, Part 2", Zuko briefly considers doing this to Admiral Zhao when Zhao is attacked by the (giant, enraged) spirit of the oceans. After a moment's consideration, he holds out a hand to save Zhao, but the admiral refuses to allow his despised rival to save him, and is swept away to what was presumably his death. It turns out Zhao really should have taken Zuko's hand since he reappears in the second season of The Legend of Korra, which shows that he was transported to the Spirit World where he became a prisoner in the Fog of Lost Souls for killing the Moon Spirit. Zhao has been driven to utter insanity there, and will apparently remain a prisoner for all eternity.
- As shown in "Avatar Day", Avatar Kyoshi let Chin the Conquerer fall to his death when she split her home peninsula off from the mainland. In "Sozin's Comet, Part 2", Aang points out to her that she didn't actually kill him, since all she did was take a defensive action by partitioning the peninsula from the surrounding area, and Chin chose to remain on what had become an unstable cliffside afterwards until it gave way beneath him. Kyoshi replies that she sees no difference between letting him die and killing him because while his death might have been an accident, she was willing to kill him if that was what it took to stop his reign of terror or if he had taken any further action against her or her people.
- Kyoshi's friend Yun got killed in her tie-in novel by his earthbending teacher, Jianzhu, in the same manner. Yun was believed to be the Avatar, so Jianzhu offered them both up to a spirit to see who it truly was. He chose to save Kyoshi once it was confirmed that she was the real Avatar but left Yun to be taken by the spirit, fully expecting it to kill him. Yun ambiguously Came Back Wrong at the climax, just to return the favor, a lot more directly.
- In a flashback from "The Avatar and The Fire Lord" showing parts of Roku's life, Sozin leaves Roku to die when Roku accidentally inhales toxic fumes from an erupting volcano, realizing with the Avatar out of the way, Sozin can proceed with his plans of world conquest unopposed.
- Bojack Horseman: It's eventually revealed in Season 6 that not only did Bojack wait seventeen minutes to call 911 when he discovered Sarah Lynn was dying from a heroin overdose at the planetarium in order to create an alibi for himself and make sure the police didn't discover he was the one who gave her the heroin in the first place, but that she didn't actually die until after she was taken to the hospital. There's no way to know for sure whether immediately calling for help would have made any difference, but once some reporters discover evidence of the incident and make it public, almost everybody, including many of Bojack's close friends and family, considers him to be responsible, especially considering that because he gave her the heroin she overdosed on, her death is still at least partially his fault even if he had called 911 straight away. He manages to avoid serious legal ramifications (the worst that happens on that front is that Sarah Lynn's parents sue him for his involvement in her death and he has to give them 5 million dollars for the settlement), but he becomes a pariah in Hollywood and among the public at large as they're all disgusted that he was willing to let somebody die like that to save his own ass. Even his friends (except for Mr. Peanutbutter) keep their distance from him in the fallout, and Hollyhock cuts him out of her life with a non-romantic "Dear John" Letter.
- It is implied in the first few episodes of The Dragon Prince that Viren acted in such a manner so that Harrow would get killed. Harrow was the king, and Viren was his wizard, and once his oldest and closest confidant. When Harrow learns that elfish assassins want to kill him, Viren offers him to save his life with dark magic. For reasons that aren't clear at the time (it won't be revealed until several seasons later that a "clever plan" Viren came up with involving dark magic is what got Harrow and elves caught in a Cycle of Revenge in the first place. Furthermore, another one of Viren's plans resulted in Harrow's beloved Warrior Queen wife Sarai being killed while Harrow, Viren, Sarai and company attempted to carry out said plan), Harrow does not want to have anything more to do with dark magic, and reacts very coldly and dismissively to Viren's offer. When Viren tries again, Harrow forces Viren to kneel in front of him while humiliating, taunting, and offending him. As a result when the elven assassins defeat the king's bodyguards, Viren does not lift a finger to rescue Harrow. He even stops Callum from coming to the aid of the king. Both certain members of the court and General Amaya either suspect or outright accuse Viren of allowing the elves to kill Harrow so he can become king himself. It should be mentioned that it is uncertain if Viren could have successfully fended off the elven assassins because they were very good assassins with magical powers and abilities that humans lack. But due to the way Harrow inflamed his pride, Viren did not do anything to protect him.
- In the Family Guy episode "Send in Stewie, Please", Stewie lets the preschool therapist he was talking to slowly die from a heart attack because he doesn't want his secrets getting out.
- Subverted in Green Lantern: The Animated Series. Sinestro uses something like this trope as a defense when his actions result in the in-custody death of Naraxis ("I didn't kill him, I just didn't save him"), but it's revealed to the viewer that Naraxis's death was anything but inadvertent; Sinestro actively manipulated events so that Naraxis would die, and actually gloated about it to the guy as he suffocated, making it just straight-up murder.
- Justice League:
- In "The Enemy Below", Aquaman confronts his evil brother Orm. who stole the Trident of Poseidon, tried to overthrow him, and put him and his baby son near a submarine volcano to kill them both off. When Orm ends up hanging over an abyss during their last fight, he shamelessly begs Aquaman to save him. Aquaman just picks up his fallen trident while coldly saying "I believe this is mine" and lets him fall.
- In "Twilight", Darkseid shows up in the Watchtower and asks for the League's help since Brainiac is attacking Apokolips. Superman, having suffered a lot at Darkseid's hands and expecting that Darkseid has an ulterior motive, only says "Good." Superman turns out to be right.
- The Owl House: A disputed occurrence is seen at the end of the series finale once Belos is ripped from the Titan's heart. It is unknown if Luz summons (consciously or otherwise) the boiling rain that ends his attempt to convince her that she has freed him from a curse and highly uncertain if she could have protected him, healed him, or stopped his deterioration; however, it is made absolutely clear that she has not the slightest inclination to try offering any manner of succor (including hastening an end to his final agonies) as he rots alive before her. Even when Eda, King and Raine decide to stomp his remains until he's nothing but dead goo out of self-satisfied payback, she doesn't intervene and just stares at him with contempt.
