This first set of justifications are only yellow flags, the kind of things which might also be uttered by garden variety narcissists.
On their tendency to fly off the handle:
"Hey -- I get angry because I care." (Implying he cares about the organization or cause, when in fact he only cares about himself.)
"I'm passionate about my work." (Translation: I have no self-control.)
On their impulsive natures:
"What's wrong with a little spontaneity in your life?"
"I don't want to be a stick-in-the-mud like Sam."
"Sometimes you have to just go with your gut."
On their grandiose sense of self-worth:
"Do you know who I am?" (Have you never heard of my greatness?)
'I'm the last guy in the world you want to mess with." (True enough.)
"This place would collapse without me." (In fact, the place would probably do better.)
On their low threshold of boredom:
"I like action, I like to stir things up a little, see what happens." (Translation: I like to upset people just because it amuses me.)
"I'm an adrenaline junkie."
On their manipulativeness:
"I'm a leader. I know how to get people to do things."
"Don't worry about that guy, I can handle him."
"I got her wrapped around my finger."
"They all think I'm a god." (When this is plainly not the case)
The statements from here on tend to be red flags.
"I just wanted you to be happy, so I told you what you wanted to hear."
"Hey, the bosses want profits, this is what I have to do."
"If they're dumb enough to believe me, that's what they deserve."
"One man's truth is another man's fiction, it's all perspective."
"Okay, so I lied. So what?" (Said in an angry, challenging manner.)
(They also like to tell you what others say about you behind your back -- even if it's not true.)
On their bullying:
"I'm a take no prisoners kind of guy." (Spoken with great pride.)
"I know I can be a little obnoxious." (When the actual behavior is far worse.)
"I hate that guy!" (For no good reason, about multiple people.)
"Hey, it's a dog eat dog world out there." (Because people like him make it that way.)
"Guy woulda done the same to me, believe me."
"Someone needed to teach that guy a lesson."
"I believe in doing it to the other guy before he does it to you." (Even if the other guy had no intention of doing so.)
"It's time for a change. We can't have a guy like that in charge." (I should be in charge.)
"If he thinks I'm going to put up with that shit, he's crazy." (Regarding some reasonable request.)
On their criminality:
"Hey, I got three hungry mouths to feed."(So I have to rip these people off.)
"There are two kinds of people in this world -- sheep, and wolves." (As if he had no choice but to be one or the other.)
"I know I've made a few mistakes in the past, but they don't define who I am."
"That was the old me. I'm a new person now." (Somehow they always seem to think you'll believe them when they tell you they got a personality transplant.)
On their lack of shame or embarrassment:
"Why should I feel bad? That motherfucker had it coming."
"No point in dwelling on the past."
"What's done is done, no point in worrying about it now."
"I just did what everybody else wanted to do." (Said with a shrug.)
(Or, they may just change the subject.)