Redcloak's failed characterization, and what it means for the comic as a whole.

[Kish]

The important thing is that Redcloak regards it as an injustice.
The paladins surely did not.
The paladins are more likely to be right, but that is not important to the story.

No, the important thing is that the author, Rich Burlew--he's been posting in this thread--called it an injustice. Therefore, it was an injustice, even if you don't consider "Redcloak's five-year-old sister deserved killing" laughably absurd. If the paladins believe otherwise than their chance of being anything but wrong are 0%.