History HorribleJudgeOfCharacter / WesternAnimation

* ''WesternAnimation/AmericanDad'': The Smith family members have a terrible judgement of character towards Roger as seen in multiple episodes as one common plotline the show uses involves one member of the family giving Roger an opportunity for some scheme or business only for Roger to backstab them. Steve out of all the smith family members has the worst sense of judgement towards Roger, to trusting him constantly and getting screwed over for it again and again, showing that Steve does not learn his lesson and because of this repeats the mistake. In one episode l, Hayley and Jeff decide to not trust Roger when he hosts a burning man event in the backyard and when they think he using the event to harvest people's organs, they are proven wrong when it's revealed that Roger harvested his own organs to fund it.

* ''WesternAnimation/BatmanTheAnimatedSeries'': "It soon became obvious to me that The Joker, so often described as a raving homicidal madman, was actually a tortured soul crying out for love and acceptance..." Doctor Harleen Quinzel (aka [[VillainousHarlequin Harley Quinn]]), welcome to the list.

** The title characters. Even when they get their asses kicked by Todd, they still think he's cool and aspires to join his gang. In fact, every single hoodlum, criminal, and {{Jerkass}} they meet is "cool" by their standards. Then again, when you consider their priorities and interests, it's not that surprising. Hell, in one episode they even "befriend" an escaped serial killer who is clearly deranged, is more or less openly planning on murdering them... and has the word "Killer" tattooed on his forehead (because they're both nearly illiterate, they read it as "Kyle-er" and think it's just his name).

* Linda of ''WesternAnimation/BobsBurgers'' is entirely too trusting of total strangers. Her innate desire to make friends with just about everyone she meets blinds her to some pretty awful, incompetent, or manipulative people.

* {{Downplayed|Trope}} with [[IdiotHero Fry]]'s friendship with [[HeroicComedicSociopath Bender]] in ''WesternAnimation/{{Futurama}}'':

* Harley Quinn herself in [[WesternAnimation/HarleyQuinn2019 her titular series]] has this in spades. Because of her horrible relationship with the Joker, she believes all men in a relationship with women act like him. This leads her to [[spoiler:assume Mr. Freeze was lying about the whole "I froze my wife to keep her from dying of a horrible disease until I can find a cure" thing and that he really did it out of a desire to control her, so she unfreezes Nora... only to find out that Mr. Freeze was very much telling the truth. Nora's disease begins progressing extremely rapidly, to the point that the only thing that can save her is a complete blood transfusion, but Nora has an extremely rare blood type. Freeze immediately volunteers to take a serum mixed up by Poison Ivy that will change his own blood type to Nora's so that she can be saved, [[HeroicSacrifice at the cost of his own life]]. Harley is completely blown way by this ActOfTrueLove]].

** Zig-zagged with Lisa in "[[Recap/TheSimpsonsS8E7LisasDateWithDensity Lisa's Date with Density]]" where she gets a crush on Nelson Muntz. (Even Bart thinks this is crazy, telling her, "I'll probably never say this to you again, but you can do better!") It's not that Lisa doesn't know that Nelson is a rotten kid, [[ICanChangeMyBeloved she just honestly believes that he might have a sensitive side, and she might be able to change him]]. By the end of the episode, however, she realizes that Nelson is rotten through and through, and they break up. Although, in a subsequent episode, she does a favor for him, and when asked why, she shrugs and says, "Well, we used to date."

* ''WesternAnimation/SpongeBobSquarePants'': [=SpongeBob=] and Patrick, due to their optimistic innocence, frequently fall into this trope. [=SpongeBob=] in particular fails to notice Squidward's obvious dislike of him. Other notable examples are when the pair releases the ObviouslyEvil Man Ray just because he says "please" [[spoiler:though in this case, Man Ray eventually decides to turn good after all]], and when [=SpongeBob=] is chased by a criminal and hires that criminal in a PaperThinDisguise as his bodyguard. Spongebob is also willing to stick up for Mr. Krabs for anything, even though Mr. Krabs is an utterly ''shameless'' cheapskate who will do anything to save a penny while thinking that he's a great boss. Mr. Krabs, at one point, ''sold Spongebob's soul to the Flying Dutchman for 62 cents.''

*** To the Earth King's credit, he does defy this trope in that he is willing to listen to evidence and openly states that he hopes the gang are lying because the implications of their statements (not just his advisor's betrayal, but being the head of state in a 100-year war and being the last person to hear that such a war is going on) are very troubling thoughts. And while the first offered piece of evidence (a bite mark on Long Feng's leg from Appa, despite the claim that he's never seen a Sky bison) doesn't flat out convince the Earth King, the King is willing to admit that the gang's story does [[IncrediblyLamePun have some leg to it]].

* In ''WesternAnimation/StarTrekLowerDecks'', [[spoiler:Nick Locarno rescues and attempts to recruit Beckett Mariner into his brand new, independent Nova Fleet, believing her to be a MilitaryMaverick who acts out in defiance of Starfleet's bureaucracy and red tape. In actuality, Mariner is a ShellShockedVeteran whose loss of her idol (and Locarno's old Nova Squadron teammate) Sito Jaxa and being involved in the Dominion War has caused her to act out so she doesn't have to be promoted and send her friends to their deaths but, in actuality, she loves Starfleet and believes in its mission]].

** Cartman's mom seems to think he's a "little angel" to the point where she doesn't even question his story about why he has a picture of him with Butter's penis in his mouth in "Cartman Sucks". She also lets him get away with murder and always takes his side, with the exception of more recent episodes ("[[Recap/SouthParkS10E7Tsst Tsst]]", "[[Recap/SouthParkS14E11Coon2Hindsight Coon 2: Hindsight]]" and "[[Recap/SouthParkS15E1HumancentiPad HumancentiPad]]").