Never Hurt an Innocent
Many villains are ruthless and uncaring about the world around them, perfectly willing to hurt innocents to further their gains, but it's not always this way. Sometimes, you'll run across a villain who, while just as greedy and self-serving, still makes sure not to hurt those around him, and is not willing to kill and destroy innocent lives just to get ahead. Offer them infinite power if they'd just kill a single innocent, and expect them to say no. Of course, that doesn't mean they won't accept the infinite power if they could get around the whole "killing the innocent" part.
Generally, this is shown as villains trying to avoid harming people who aren't involved, and making sure not to kill innocent people. Unfortunately for our heroes, they don't count, so they can expect every weapon at these villains' disposal to be aimed at them.
This is a must for the Hitman with a Heart an Anti-Villain, Noble Demon, or Anti-Hero, a form of Even Evil Has Standards, and is a Sub-Trope of sorts of Affably Evil. See also A Lighter Shade of Grey, when something like this makes them look good despite a total willingness to kill the guilty, and Punch Clock Villain, for villains who take this to the next level, and only act villainous because it pays the bills (though it's not a given that they'll be like this). A Blood Knight may also exhibit this, although in their case it may be more down to innocents never putting up a good fight. Don't expect Omnicidal Maniac and Psycho for Hire to adhere to this trope.
In some tropes, specific groups may come pre-labeled as innocent or not involved:
- Children, in Wouldn't Hurt a Child, because Children Are Innocent.
- Women in Wouldn't Hit a Girl. Expect this villain/antihero to be a Wife-Basher Basher as well.
- Noncombatants, in Would Not Shoot a Civilian.
- The injured, in Kick Them While They Are Down.
- The Medic.
- The Good Shepherd, if an Actual Pacifist.
- Those whose opposition is honest but misinformed; Would Not Shoot a Good Guy tends to be heroic.
May be a form of Villainous Vow. Pay Evil Unto Evil is the kind of antagonism permitted to characters following this trope. Antonym of You Can't Make an Omelette. This trope is generally ubiquitous in heroes so list villains and antiheroes here.
- Light in Death Note thinks of himself as this; his stated intention is to kill all the criminals in the world to make it safe for innocents. But he's really bad at that in practice. As soon as he hears that L plans to stop him, he shifts right into "all who oppose me must die" mode.
He manages it alright during the Yotsuba Arc, where it's shown (as if we weren't already aware) that his morals when he doesn't own a Death Note are an almost direct lift from his father- which brings them both into conflict with L.
- Mahou Sensei Negima: Just about every major villain to appear generally falls into this. Chao took great pains to see that no one would be injured, and Negi is the only person that she actually fought seriously against. Later on, Fate has stated that he has no desire to hurt anyone except those who are actively opposing his plans, and that the only person he actually wants to kill is Nodoka, as her Telepathy makes her too dangerous to his plan. It's actually a bit of a Double Subversion, as his ultimate plan seems to be erasing the magic world from existence, but he thinks that he's doing everybody a favor.
Even the demons summoned in the Kyoto arc (not counting the Demon God); when they just think they're being sicced on "ordinary teenage girls" assure Asuka and Setsuna that they'll just beat them up; not kill them or anything.
- The two anti-villains of Fullmetal Alchemist (any version), Greed and Scar fit this. Greed, particularly his manga equivalent, is greedy for followers, so he has no interest in harming innocents. Eventually, he actually tries to save people. This is a sharp contrast to the rest of his siblings. Scar starts off as a Serial Killer targeting only State Alchemists, generally those who fought in and committed genocide during the Ishvallan War, although he also tries to kill the protagonist.
- Kanone in Spiral has a strict rule to only kill Blade Children. This is something that is used by Ayumu to help defeat him. Kanone has amazing reflexes, but he always makes himself pause for a moment to ensure he is not killing a normal human rather than Blade Children. So Ayumu takes advantage of that.
- While Tiger and Bunny's Lunatic will kill criminals and attack people who aid criminals (like, say, heroes trying to prevent his assassinations), he won't hurt someone he sees as innocent according to his moral code. So when he realizes that Kotetsu has been Unpersoned and framed for murder, he's the first to help him out.
- Vegeta invokes this when he attempts to defend Goku from Metal Cooler.
Vegeta: "You'll spill no Saiyan blood this day! ... Your fight is with me, now. Kakarot's fate is no longer your concern!"
- Given that he has shown no qualms in killing other innocents, this is really more an application of The Only One Allowed to Defeat You.
- X-Men: Depending on the Writer, Magneto can be one of these. It's generally a given that he won't take a mutant life if he can help it, and, if he's one of his less megalomaniacal moods, will avoid attacking humans that aren't his targets or against him (in his other moods, all humans are his targets).
- The Flash's Rogues Gallery is generally made up of people who probably wouldn't make a plan around shooting an old lady crossing the street. Explicitly stated a few times as something of a survival strategy. They really don't expect superheroes to intentionally kill them, but they know being homicidal maniacs will bring more than just the (usually rather reasonable, and sometimes even friendly) Flash down upon them. Many of them are also probably self aware enough to know that their issues combined with killing needlessly would probably land them somewhere like Arkham, and they know they don't want to be cooped up with the kind of people that wind up there.
- Deadpool criticizes a group of mercenaries who saved him from jail by killing everyone who was guarding him. When they insist it doesn't matter because they're just cops, Deadpool snaps back that they were only trying to protect their people (the town was currently infested with zombies... long story). And then he kills them all and goes on alone.
- The Hulk is like this. He may rage to high heaven and destroy an entire city, but he has never killed anyone deliberately... or even accidentally! Best not to think about the latter too much. Ultimate Hulk is, quite graphically, as far from this as you can get. Then came the "Heart of the Monster" story arc in Incredible Hulks when he wound up in the Dark Dimension. Where no one is innocent. And his ex-wife and his worst enemies were there too.
- Venom from Spider-Man, Depending on the Writer. Even during those times, though, even if he'd never hurt anyone he decided was innocent, it's hard to know who will or won't fit the criteria (due to his being Ax Crazy, if less so than Carnage.)
- In the MAX series at least, this is one of the reasons The Punisher is an Anti Hero. He takes great pains to avoid civilian casualties while he's gunning down dozens of Mooks, and at one point he nearly kills himself because he thinks he shot an innocent. The mainstream Punisher, depending on who's writing him, is portrayed as trying to not kill innocent civilians or the superheroes who try to stop him. Of course, other writers have had him attempting to gun down jaywalkers. And he did kill off his sidekick's girlfriend while brainwashed, though at an earlier time, being ordered to kill Spider-Man (an innocent) broke the brainwashing a different villain subjected him to. 
- Demogoblin; a demonically possessed variant of the Green Goblin/Hobgoblin/etc. from the Spider-Man universe was out to kill all sinners in the world. His final death was saving a mother and child from a collapsing church.
- Skurge the Executioner fought on the side of evil in an effort to win the love of Amora the Enchantress. However, he was brave and noble, and never attacks anyone besides his target. In one story, Thor realized the Skurge he was fighting was an imposter because the fake slapped a child in his path.
In The Superhero Squad Show, he surrenders when he accidentally knocks a frozen solid Valkyrie off a building, where she would have shattered if Thor hadn't caught her.
Skurge: (while using a heat blast to defrost Valkyrie) "My mad love for Amora almost cost an innocent's life!"
- In the X-Men films, as above, Magneto is usually like this. In the 3rd film a family are trapped in their car when the bridge is moved, and once it is moved, Magneto notices them, frowning in surprise. The mother locks the door and he turns away smiling. He also seems not to toss that particular car, and with a couple of notable exceptions (Rogue and possibly the policemen guarding Mystique), most of the people he kills are cases of Jerkass Victim (e.g. the security guard and Stryker). The exception is attempting to turn Stryker's plan in X2 around to kill all non-mutants, though that was more impersonal.
- John Q: The only thing the main character cares about is his son, and has no intention of killing anyone.
- Inside Man: The robber running the bank job will not hurt anyone who doesn't force him to do so, kills no one, and is actually trying to bring down someone who did kill many innocents.
- The Rock: Francis Hummel he takes innocents hostage and threatens to launch a chemical strike at San Fransisco, but he refuses to harm any of his prisoners and deliberately sabotages his own missile launch to avoid civilian casualties. And just before he takes over Alcatraz, he has a bunch of kids on a field trip and their teacher get out of the complex.
- Predator: The Predator species generally avoids killing unarmed opponents, since they considered it poor sport.
- Ken, Ray and Harry from In Bruges are very specific about never killing anyone who is innocent (particularly notable with Harry since he is otherwise quite sociopathic). At one point, Harry is very careful not to shoot in a crowded area, and both he and Ray adamantly refuse to fight with a pregnant woman standing between them. When Harry believes himself to have accidentally murdered a child at the end, he immediately commits suicide because he considers what he has done to be unforgivable.
They mostly adhere to this. Given their profession, it's more like never hurt an innocent without a "good" reason. Children are the main way it's played completely straight - while the story is the result of Ray accidentally killing a child, and Harry commits suicide because he thinks he did, the child Ray killed was behind his target, a priest who just got in the way of Harry's business. Ray does assume he was following this fairly closely until he finds out about that, though.
- Leon, Léon: The Professional, has very simple rules about his clients: "No women, no kids, that's the rules."
- In Terminator 2 John Connor tries to get the T-800 to do this by asking him not to kill anyone. The terminator complies by shooting a security guard in the knees. When John protests the terminator coldly responds "He'll live."
- Scarface: One of Tony Montanna's good traits. He blew the brains out of an assassin he was supposed to drive around because he was willing to kill the targets wife and children just to get him.
- In Jumanji, Egomaniac Hunter Van Pelt is summoned by the game to hunt Adam, who rolled him up—but, as it turns out, only Adam. Van Pelt can't or won't directly harm anyone else (and Lampshades this), though he has no compunctions on collateral damage in the process of slowing Adam down, as long as nobody else gets anything worse than an inconvenience.
- Artemis Fowl: When Artemis is accused of being just as bad as the current villain, he uses this trope as a defense.
- The Thrawn Trilogy:
- Commander Thrawn tries not to kill anyone who isn't his enemy. He'll fire at Vagaari ships, which have Living Shields, saying that they are already dead; if the Vagaari's tactics don't kill them in this battle they will die in the next, and stopping the Vagaari now will save more people in the long run, but he's unhappy about doing this, and makes plans to avoid it in the next engagement. This may be an extension of his species' brand of Martial Pacifism, although Thrawn himself ignores their rules whenever they're inconvenient. He is deeply, deeply unhappy about what happened to the fifty thousand innocents on Outbound Flight. In his defense, he wasn't the one who killed them.
In Outbound Flight he's about as non-evil as Thrawn gets. In later-set novels, while his plans and tactics show him to be A Lighter Shade of Grey and he avoids killing innocents when possible, he's very much more pragmatic.
- The stormtroopers who later formed the Hand of Judgment got in trouble with the Imperial Security Bureau because at least one of them refused to shoot unarmed civilians, never mind that they were supposedly Rebels. This lead to him semi-accidentally killing the ISB officer who confronted him with a blaster, which led to him and his friends deserting. That same stormtrooper, LaRone, who aimed to miss ended up being the leader of the group; another of them explains how, ending with the fact that refusing to kill innocents gives him the moral high ground. Confused, LaRone says that he thought all of them did that, and he is told "I obeyed orders."
- The Dresden Files: One of the things that makes "Gentleman" Johnny Marcone a Noble Demon (despite being The Don of Chicago) is the fact that he goes out of the way to ensure children never suffer the ill effects of his "business". If someone in his organization hurts or sells drugs to a child, God help them.
- Going Postal: This is something Moist von Lipwig prides himself on. Subverted when Pump 19 tells him that Moist's cons and scams, while not hurting anyone directly, have caused harm equivalent to the murder of 2.338 people. This is brought home when he learns that a previous job of his working to defraud banks working with bonds and letters-of-rights made his love interest lose her job.
- In the TV adaptation, the number of people Moist "killed" increases to 22.8 and his fraud causes the bankruptcy of his love interest's family (and gave the book's Big Bad the opening he needed).
- The assassins from Assassins Guild could be argued to fit this trope. They would never kill (or ‘inhume’ as they call it) someone unless they are paid to do so and the victim (client) must have a sporting chance. They won’t take out a contract on someone who can’t defend themselves but if you can afford a bodyguard then you’re automatically deemed able to do so. They prefer to inhume their clients at there place of work or at home rather than the street. Although, it’s accepted for them to inhume a client’s bodyguard or another assassin while performing their service, they wouldn’t dream of killing an innocent maid who just happened to be in the house at the time. They are polite, efficient and will even clean up afterwards.
- Dexter: Dexter makes a point of only killing other serial killers. Even apart from the Code of Harry forbidding him to harm innocent people, he's disgusted by the idea that anyone could harm children, though for the most part he kills other murderers because it causes less trouble with the authorites when they go missing or turn up dead that out of any true condemnation of their activities, though that does occur on occasion.
- Sylar in Heroes has made it clear that he doesn't just kill people for fun - only if he needs their powers. On the other hand he has also made it very clear that he does enjoy killing people - even continuing to mutilate his victims after figuring out how to replicate their powers without doing so and commentating that he almost forgot what fun it was. Apparently the thrill of it is not enough to go after ordinary, and therefore useless, people though.
- In season 1, when Sylar first comes to the (incorrect) realization that he is the bomb that will blow up New York and kill half the population, he goes through utter turmoil, asking Mohinder for help. According to him, he only kills because he sees it as an evolutionary imperative that he acquires new powers. He only kills evolved humans who have powers he wants. He does not want to kill 4 million regular humans. He eventually gets over it after (inadvertently) killing his mother.
- From The Wire, Omar Little, Badass Extraordinare, has a code of honour that means not hurting anyone who isn't in the Game. No doubt.
- This is one of the rules of Assassin's Creed.
- Hitman: It varies. While Agent 47 is very much into Pay Evil Unto Evil, he only cares about his contract, and will kill innocent people if he's paid to.
- Fate/stay night: Lancer, mostly, because innocents are no fun to fight. He still 'silences' Shirou when the latter ends up causing a Masquerade Violation, but clearly doesn't like having to do it.
- In Mass Effect 2, Justicar Samara's code prevents her from ever hurting an innocent person, even if she must allow a criminal to escape in order to prevent it. Apparently, this tenet of her code is overidden if that innocent person poses any threat to the Justicar herself or attempts to impede her investigations.
- In The Godfather: The Game, while you can freely indulge in Video Game Cruelty Potential while free-roaming, some missions ask you not to kill innocents. Inverted in one contract hit, where you need to ensure there are no witnesses for the Respect and monetary bonuses - guess what?
- In Endstone, Colindra rages against the would-be rapists because she had seemed innocent and in need of help.
- In the inn scene of The Order of the Stick, the assassins who are after the king of Nowhere try to avoid hurting anyone who is not involved. Too bad they think that Roy is the king of Nowhere.
- Dr. Horrible of Dr. Horrible's Sing-Along Blog is this way, at least at first. He refuses to fight a hero in a park because children play there (well, that and he doesn't have time to fight every "poser in a parka"). He also tells a room full of civilians to flee before he tries to off the hero, Captain Hammer. Plus the fact that he never really crosses over the Moral Event Horizon completely shows that, even after getting a seat on the Evil League of Evil, he still has problems with truly hurting innocents.
- Agents in the Protectors of the Plot Continuum generally try to either recruit non-Sueish bit characters or let them assimilate into the canon. They also tend to do their best to save Sues' kids.
- The Nostalgia Critic has a breakdown when his anger over Quest for Camelot makes him accidentally kill Mary Poppins, Dick Van Dyke and Mickey Mouse.
- Phantom 2040: Poignantly, The Dragon cyborg Graft stopped a fight he was winning when a kid got endangered.
- Sandman in The Spectacular Spider-Man was never truly malevolent, he was just in the villainy game for the money, and hoped having powers would finally get him the "big score" he always wanted. In episode 18, he helped save the passengers of a ship about to explode. A ship he was trying to rob until his fight with Spidey started a fire.
Spider-Man: "Sandman, stop! You..." *watches Sandman place the crewmen he'd grabbed into the life rafts* "...saved them?"
Sandman: "I was just in it for the bucks. I never meant for this to happen."
- My Little Pony Friendship Is Magic: A non-villainous example appears in "Griffon the Brush Off". Pinkie Pie and Rainbow Dash have a fun day pulling practical jokes on their friends in Ponyville, except for Fluttershy, whom they leave undisturbed because she's too innocent and sensitive for their pranks.
- Red X from Teen Titans seems to follow this principle—and it even applies (in a general sense) to the heroes. He's perfectly willing to curbstomp them and taunt them about it, but he's not trying to kill them and refrains from attacking them when they're down. Similarly, he's quite happy to steal expensive items from corporations, but when a supervillain threatened the city with a disintegrator cannon and Robin almost fell to his death, Red X saved Robin's life and helped him defeat the supervillain rather than make a clean getaway.
- The innocent was already dead, and the situation was set up so that he would think he killed her. Castle only realizes this when he exhumes the corpse and compares the bullet wound to his weapon.
- In one of his earliest appearances, it's said that he had vowed to turn himself in if he ever killed an innocent. In the final story arch of his original series, he nearly goes through with it too after accidentally gunning down a family (it was later retconned that he wasn't the one who killed.)