Assassination's hard to justify when you're not at war, it's generally called "murder".
Kate Ashfield - Rachel

The "big red dog" is diggin' in our backyard, and we are justified in shooting him!

Kevin Conway - Gen. Curtis LeMay

“- Richard 'Dick' Brewer: Rumor has it you killed a man, Billy. You don't seem like the killing sort.
- Dirty Steve Stephens: Yeah, Billy. What'd you kill him for?
- William H. 'Billy the Kid' Bonney: He was hacking on me.”
Charlie Sheen - Richard 'Dick' Brewer
Dermot Mulroney - Dirty Steve Stephens
Emilio Estevez - William H. 'Billy the Kid' Bonney

“- Shaun: I'm so sorry.
- Phillip: Sorry for what?
- Shaun: Er… nothing.”
Simon Pegg - Shaun

“I didn't kill him. Maybe the guy cut himself shaving and bled to death looking for a Kleenex?”
Eddie Murphy - Chandler Jarrell