Sarah Walker from Chuck killed an unarmed man. He was threatening to expose Chuck.
Yeah, the kill limit doesn’t fill by itself you know.
That was a great episode. But, I thought that LaForge disabled the phaser in transport, so it was unclear to me if Data really got him or not. He was certainly trying to, but I thought they left it unsaid whether the collector was killed. (Going off 19-year-old memory here, though). Either way, not only does Data try to kill him, he … misleads the crew upon his return. LaForge or Chief O’Brien or somebody says, “We detected a phaser firing”, to which Data replies, “Perhaps something occured during transport.” Awesome ending.
You might be thinking of a scene in Doctor No in which a bad guy (a medical doctor, though not the title character) repeatedly shoots Bond in his sleep, but it’s a ruse since Bond filled the bed with pillows and such and is waiting in hiding with his own gun drawn. Bond orders the would-be killer to drop his gun and starts monologing, while the shifty-eyed bad guy pulls a throw rug toward him with his shoe, inching his dropped gun closer and closer, until he suddenly reaches down, grabs it, points it at Bond, pulls the trigger… and the hammer clicks down on an empty chamber.
“That’s a Smith and Wesson, Doctor,” observes Bond coolly. “And you’ve had your six.” Then he shoots the bad guy and put a second round in his back for good measure.
As far as I know, Bond wouldn’t shoot another unarmed opponent until The World is Not Enough nearly forty years later.
IIRC, the whole point is that there’s only one shot in Stromberg’s under-the-table speargun in THE SPY WHO LOVED ME; that’s the only reason why Bond is able to put his pistol’s barrel in the tube, relish the situation for a long moment, and then fire through the now-empty gun to shoot the guy – before then firing a second round for good measure.
I must’ve blanked out on that one. It was a silly movie, anyway.
When Giles took the Potentials off on a vision quest, the gang thought he might have been the incorporeal First Evil, because no one could remember him touching anyone. Upon verifying that he was, in fact, solid, his response was:
“Because I took a bunch of underage girls camping and DIDN’T touch them you think I’m evil???”
Not sure if if counts, since she didn’t kill him herself, but she dropped off a handcuffed gang leader in a rival gang’s territory, announcing it on the car’s loudspeaker as they drove in.
It was in the first or second season.
Data didn’t shoot the man, he was transported before the weapon went off. That’s why Riker questioned Data about the energy discharge during transport. Data lied and said it was a misfire caused by the transport. I got the feeling Riker didn’t believe Data, but let it slide. Data later confronts the man in a prison cell on the Enterprise.
I think there’s a couple questionable cases in “Have Gun Will Travel.” Paladin generally avoids the fight if possible, but I think there’s a few cases where he doesn’t avoid it as well as he could. I’d have to rewatch to name any specific instances, but I remember watching the first season on DVD and thinking, “Hey…that’s kinda sketchy” a couple times.
Mal’s “kick into the engine” in Firefly definitely counts.
You could very easily argue that Kirk murders Edith in “The City on the Edge of Forever.” Sure, it’s the classic question of “is letting somebody die murder?” but Kirk took an active step to make sure she was allowed to die. Sure, it was the right move, but, hey. The OP didn’t say it had to be WRONG.
And of course there’s the episode of Frasier where Niles stabs Maris to death with a meathook (offscreen, naturally).
Also on Homicide: LOTS (specifically the wrap-up TV movie): Tim Bayliss, a character who always seemed very gentle, may or may not have killed a suspect who escaped prosecution (it’s strongly implied).
Cosmpolitan just posted mine. 
More than implied; in the wrap-up movie he confessed to Pembleton that he did it (because he knew Pembleton would have to arrest him for it).
He does in Tomorrow Never Dies, as well (though you might argue against the “unarmed” part, on a technicality).
I’m not sure how this fits the OP, but this incident begins the character’s long, slow spiral down the drain.
What? No mention of
Munch killing that Pratt guy played by Steve Buscemi? That did embolden Bayliss to cross the same line, although it was left as a possibility that Munch was covering for a different detective.
Then again; Data was designed to be flexible. Capable or learning and changing. Just because he WAS programmed a particular way doesn’t mean he’d stay that way. When the bad guy killed this woman who helped Data, Data finally said “I cannot permit this to continue” and pointed the phaser. I consider it a moment of personal growth.
IIRC, the man talks about how he’ll get out and add Data to his collection sooner or later. And Data tells him that no he won’t; all his “collected” goods are being returned to their owners. The collector says Data must enjoy his victory and Data says something like “Enjoy? No, I do not. I feel nothing. I am an android.” and walks out. Which in context was something of an extra slam to the guy who had been treating him as an object.
Nobody’s done B5 yet, have they?
Vir’s killing of Caligul…I mean Cartagia is not exactly cold-blooded, but certainly deliberate. Not just murder, but treason too.
Londo has Morden killed - legally not murder 'cos hey, he’s the Emperor he can do what he likes, but morally very cold-blooded.
G’Kar is involved with the lynching of Lord Refa in the end of “And the Rock Cried Out” … I don’t remember if he actually stayed for the kill though
Wow, I’d forgotten that whole part. I always thought it ended with Data beaming back aboard.
In L.A. Law, Tommy Mullaney shoots a serial killer in cold blood. Link
Not a TV episode (yet), but a book. In one of the Hercule Poirot stories, Poirot himself murders someone who is himself a multiple murderer, but cannot be convicted. I won’t identify the book. I dare say David Suchetwill film it eventually. They are intending to film all of the Poirot stories.