Several examples throughout the series; one very common type is a character who, while not the killer or even usually an antagonist at all, played a major role in initiating the chain of events that climaxed in the murder. It's also common with the Sympathetic Murderer, who is often not really that sympathetic at all. Examples include:
- The killers from "The Hitchhiker" and "Dog Day Afternoons". The former, even as a loser who seems to be an Unlucky Everydude frustrated with his circumstances, feels that killing his distant cousin out of both jealousy and to get his money justifies his act. The latter, who is the Lesser of Two Evils between him and his sociopathic cousin and partner-in-crime, is still a spineless wimp who killed an innocent woman just because his partner goaded him to.
- The killer in "The Letter". Yes, his girlfriend was being violently gang-raped by his friends. But he didn't do anything to stop them and, even considering that, suffocating a person so she doesn't have to live with the trauma of being raped seems like...a decision that should not have been left up to him. Not to mention keeping quiet about the crime for decades (which caused his girlfriend's daughter to think the worst about her mother her whole life and let the head rapist die scot-free), and not even immediately coming clean to the detectives when they reopened the case.
- Audrey Metz, the victim in "World’s End". It's less that she deserved to die for cheating on her husband, and more that it's portrayed as a feminist victory although it is totally avoidable in every way.
- The girlfriend from "Family" who, even as a Broken Bird, still abandoned her baby in a garbage can in the caretaker's closet. In-Universe even she acknowledges this, regretting not at least leaving her daughter in a hospital or church.
- The fathers from "Jackals" and "Blank Generation". One was imprisoned for a despicable crime (stealing benefit payments from disabled and dead veterans) instead of being on the outside and protecting his daughter while the other was an Insufferable Genius Jerkass whose cold, unloving attitude, even after his wife's suicide, drove his son to join a dangerous cult.
- The father from "Justice". His 18-year-old daughter was date-raped and when she came to him and told him what happened, his response was "Nice girls don't invite boys up to their room." As a result of his words, the poor girl ends up eating her gun. It's only then that he's remorseful and says to the (sympathetic and willing to help, but her superiors didn't take the matter seriously) investigating police officer, "Why didn't anyone help my little girl?"
- The victim in "The Key" dives headfirst into this trope. She's the only person in her inner circle of friends to not want to screw around with somebody's partner but her hubby disagrees, so she decides to give it a go and falls in love with her fellow adulterer, but decides she doesn't need a man in her life. Sounds fair, right? Well see, the thing is that during these revelations, she discovers that shock horror, her new man and best friend's husband isn't interested in staying loyal to her. How does she retaliate? By bumping and grinding against his fifteen-year-old son at her daughter's birthday party. Oh, and it gets better — she's actually surprised when aforementioned son gets the wrong idea!
- Leah, the victim's female "friend" from "Wishing". To wit, she had a crush on the boy, a mentally disabled classmate, and when she goads him into kissing her, her boyfriend walks in on them, she claims he took advantage of her, he and his friends beat the kid up, her parents press charges, and he winds up being mercy-killed by his teenage guardian. She could have told the truth ages ago, but let the subsequent tragedies happen to save face (and out of a naive belief that he'd be happier in another school) and is now deservedly left with her guilt.
- The victim's Fat Bastard best friend Butch in "Kensington". He was intended to be shown as a man broken by the loss of his job, but just came off as a dick who taunted their other friend, an unstable man, into accidentally stabbing the victim to death, after the latter managed to calm the man down. Unlike the others, however, he is actually punished; as he witnessed the murder and did nothing, the cops arrest him as accessory.
- The mother and the killer from "Time to Crime", but particularly the mother. The former cheats on her hard-working husband out of "loneliness" with a slimy, serial cheating Arms Dealer and still tried to get him back even after learning that he cheated on her, causing the murder in the first place. The latter ended up killing his younger sister in a drive-by shooting when he tried to shoot the dealer in a public park instead of at the moment he received the gun from him.
- Scotty at times. There were so many bad things that happened to the people close to him (his mother's attack, his brother being molested as a kid and haunted by it, and his ex-fiancée being institutionalized and committing suicide), but these things happened to them instead of him. In addition, a lot of the bad things that occurred in his own life, such as his suspension, were of his own doing.
- Doreen from "Disco Inferno" is a Manipulative Bitch who seduced a horny teen to injure a rival dancer, which set off a chain of events that led to the murder of said dancer plus 22 others in a deliberately lit fire, one of the deadliest in the series. The problem is that Doreen slept on that information for 26 years, and suffered no on-screen punishment for it. In real life, she could have been charged with incitement.
- Both the Alpha Bitch and (to an extent) her older brother in "The Sleepover". Even with having abusive parents growing up, in the present, she remains a self-serving bitch who doesn't even care about the victim or her cohorts in crime, and has spent years blackmailing the killer for her own benefit. Her brother is more sympathetic, but he still killed another woman in a similar way as the victim for no good reason (she reminded him of the victim).
- The killer from "Schadenfreude", Kitty, was the best friend of the victim Lindsay, who gave her a job after the family fell on hard times and stuck by her. She also slept with a mobster after Lindsay rejected his proposition for sex in order to stage a robbery for insurance. However, she never informed Lindsay, who later changed her mind on the robbery and tried to talk Kitty out of it shortly before it was to begin. Kitty then picked the worst time to reveal to Lindsay what she sacrificed to get the job going, and feeling betrayed by her friend's refusal, she shot her in a moment of anger. While there is a lot of sympathy for the lengths she went to help her friend, she nevertheless stood by for 23 years while an innocent man, Lindsay's husband, was jailed for the murder.
- The victim of "The River", Dr Grant Bowen, was a gambling addict surgeon who drove his family apart and gambled away his son's college money. To get his family out of the financial situation he caused, Grant purchased $1 million worth of life insurance and pressured his fellow gambling addict friend Cy to shoot him and Make It Look Like an Accident. While his family got the insurance payment, Cy has to live with guilt for the rest of his life, and an innocent man was arrested for the shooting, dying in prison.
- "A Dollar, A Dream":
- The eldest daughter came across as incredibly spoiled, always blaming her mother for not being able to fix the horrible situation they were in. She doesn't seem to have changed much in the present, acting just as moody and self-centered; when she finds out her mother was actually killed, she changes her stance from "her mother abandoned her and her sister" to "her mother killed herself to get away from them." It can be seen as a form of Laser-Guided Karma that her life turned out completely different from her sister's, proving that despite her supposed cynical realism, she wasn't able to build a real future either.
- The mother didn't come across as much better. Her refusal to face reality was partially responsible for their situation, and she kept it up with lies and false promises to her daughters, which were clearly for her own benefit, not theirs. Her killer was a glimpse into how she could have turned out living in that mental state long enough.
- James Hoffman in "Knuckle Up". After discovering the academic rigging in the school, he became disillusioned and joined the fight club. When his father confronts him about it, James lashes out at him, blaming him for chasing their mother away and scraping his neck.
- The killer in "It Takes A Village" barely avoids this, and is still probably a lot less sympathetic than he may have been intended to be. However one sees the childhood incident (see Alternative Character Interpretation), he doesn't go after his tormentors or people who are actually like them in terms of hurting others. Instead, he picks random children based on their performance in a video game. Not to mention that his Motive Rant makes him come across as having a serious god complex.
- The hypocrisy and sheer patheticness of the killer and victim in "Lonely Hearts" make them this. Especially since they, not the con artist, were the ones who escalated it to that point.
- Done in-universe in "Strange Fruit". While one of the suspects questioned didn't have anything against the wife of the killer personally, the fact that she was ignorant of the goings on in her own home made him not like her.
- The killer in "Officer Down" due to being Too Dumb to Live, though this may have been intentional as the cops had to force themselves not to shoot him.
- Nick on occasion. The events of "Flashover", in which a man he wrongfully accused of murdering his children some years ago has been killed in prison, causing Nick to go into a downward spiral involving drunk driving, finding out his ex-wife has remarried and had children with someone else, and temporarily getting suspended, come off as Laser-Guided Karma more than anything else.
- The best friend from "Detention". Even with an Alcoholic Parent and him knowing that the death he caused was an accident, he still went on to become an addict for years to "honor" his friend and tell everyone under the sun that he committed suicide. Not to mention that he allowed his friend's loving parents and girlfriend to believe for a decade that he took his own life and sat on knowledge of the girlfriend's stepfather's abuse of her.
- The mothers Sandra Riley and Tina Bream from "Revenge". One blatantly ignored her husband molesting her son as well as kidnapping other kids to molest because she enjoyed being Hot Guy, Ugly Wife. While she eventually felt guilty and came clean to the victim's mother, it was only after the boy was killed and even then, she never went to the police. While the other constantly enjoys Playing the Victim Card, repeatedly blaming others for her son's death even though both his kidnapping and their failing to retrieve him was entirely her fault. Not to mention causing her husband to be consumed by guilt.
- Betty Sue Baker from "Pin Up Girl". Even with her troubled upbringing where she has to strip to support herself and her alcoholic, abusive father, the fact that her best friend/cover girl Rita had a similar childhood yet was able to make something of her life undermines this. Also, while Rita gave Betty numerous outs for her situation—i.e., "I can give you money", "You can stay with me", etc.—Betty still had no real desire or common sense to better her life, blaming Rita for the Jerkass she had a date with, who only went out with her to get an autograph from Rita, and shot her out of drunken jealousy, then tried to "atone" for her crime by becoming a goody two-shoes nun who ostensibly cares about people (and which she tried to invoke right before she was arrested).
- Emily Jacobi from "Stalker". You can understand her frustration over the family's financial situation, her loneliness, and even her self-loathing in letting herself go weight-wise, but none of them were adequate reasons to not only catfish a mentally unstable man, but to use pictures of her own daughter to do so. Had she not engaged in this, she, her husband and their son would still be alive and their daughter never would have been viciously attacked or left with a guilt complex. And to add further insult to injury, the man poses as a nurse to stay close to said daughter and when she finally remembers, he takes her and the rest of the main cast hostage, resulting in Lilly getting shot and Scotty shooting the man dead. In the end, Emily is responsible for getting four people (including herself) killed and almost causing the deaths of Lilly and Kim.
- Celeste from "Stand Up and Holler". Being coerced into a gang-rape, humiliated by your teammates, and horribly torn up about what you did would normally be more than enough to make you a Tragic Villain. Problem is, the victim was Rainey, her best friend, who she let die after Rainey threatened to expose the crimes the cheerleaders and football team did to them just so she could keep being popular. Not only was it painfully obvious how cruelly Celeste was treated by them, but her claims they're all she has left ring hollow when Rainey was the only one who genuinely cared about her, and instead makes Celeste seem no different from Coach Pruit, who is treated In-Universe like someone so desperate to be In with the In Crowd that it just makes him look pathetic instead. So her subsequent remorse just sounds like she realized too little, too late that her 15 Minutes of Fame were up, and she threw everything away for nothing.
- Kateryna from "Cargo". While she was a victim of human trafficking with a Dark and Troubled Past as a Sex Slave, and ultimately just wanted someone to save her like Mike tried doing for Lena, her selfishness makes her this. Not only does she try seducing Mike so he'd take her and abandon Lena, she proceeds to kill him despite him telling her he'd come back for her once he saved Lena, then burns his feet with a cigarette butt to frame her traffickers for his death, steals and sells his boat, and lies to Lena by claiming Mike abandoned her, all so she can buy her freedom alone and make a life for herself. Over the next two years, she never tried to help Lena and when arrested, even has the gall to claim she sacrificed a lot to earn her freedom, and that Mike was no different from the many men who abused her. Self-serving and willing to damn Lena if it meant saving herself, it's hard to feel bad for Kateryna when she's arrested.
- The victim, Dan Palmer, from "Two Weddings". Most can't imagine the pain and anguish of having a loved one in a persistent vegetative state and agonizing over if they should "move on" or not. However, this still didn't give him the right to abandon his loving fiancée Anna on the night of their wedding to go back to the wife he supposedly loves but has kept a secret from Anna for all this time simply because she said his name. Then, upon learning his wife died shortly afterwards, he jumps to his death, leaving Anna to both grieve for him and wonder for two years who "murdered" him. Not helping matters is that he remained close to his best friend, even though he was the one who caused the accident that ultimately killed his wife.
