"Dumbledore isn't fond of the Azkaban guards," said Mr. Weasley heavily. "Nor am I, if it comes to that [...] but when you're dealing with a wizard like Black, you sometimes have to join forces with those you'd rather avoid." (4.3.39)
Arthur helps set up one of the major moral dilemmas of this novel: is it ever OK to team up with bad things or to do bad things in order to fight evil? Do the ends justify the means? Arthur implies that they do here, but Dumbledore's intense dislike of the Dementors implies that he disagrees.
"Dad had to go out to Azkaban one time, remember, Fred? And he said it was the worst place he'd ever been, he came back all weak and shaking [...] They suck the happiness out of place, Dementors. Most of the prisoners go mad in there." (6.1.13)
The details we hear about Azkaban start to cast the wizarding community in a very different light. Before, all we knew of the wizarding world came through places like Hogwarts and Diagon Alley – cool, fun places. Details about Dobby, the Malfoys' mistreated house elf, didn't seem to apply to the entire wizarding community, just to the "darker" Voldemort-following ones. But Azkaban is an institution that "good" wizards support and use to lock up "bad" wizards. So, is Azkaban "cruel and unusual punishment," or is it morally justifiable?
"Dementors are among the foulest creatures that walk this earth. They infest the darkest, filthiest places, they glory in decay and despair, they drain peace, hope, and happiness out of the air around them. [...] If it can, the Dementor will feed on you long enough to reduce you to something like itself [...] soulless and evil. You'll be left with nothing but the worst experiences of your life. (10.2.33)
Dementors make Voldemort sound like the Easter Bunny. OK, not really. The Dementors really represent all the darkness that Voldemort channels in his campaign for world domination. It's fitting that we focus on the Dementors in this book rather than on Voldemort himself. This novel deals with the past and, in a way, the Dementors are Voldemort's past – a legacy of darkness and evil and other bad mojo that Voldemort draws upon in his own evil deeds.
"But when a wizard goes over to the Dark Side, there's nothin' and no one that matters to 'em anymore." (10.3.164)
Hagrid has clearly not seen Star Wars. Though we somehow doubt Voldemort is going to turn out to be an Anakin Skywalker. He's the Emperor, if anything.
"Yeh can' really remember who yeh are after a while. An' yeh can' see the point o' livin' at all. I used to hope I'd just die in me sleep [...] When they let me out, it was like bein' born again [...]" (11.2.84)
We love the contrast between what Hagrid is saying (deep, profound thoughts about depression, imprisonment, and the spiritual rebirth found in freedom) and how he is saying it (in his typical local dialect). Hagrid consistently shows in this novel that you should never judge a book by its cover – he may look fairly "simple," but he has a lot of depth.
"Tell them whatever you like. But make it quick, Remus. I want to commit the murder I was imprisoned for [...]" (18.10)
Sirius's need for revenge has pretty much blotted out any clear sense he has of right and wrong. Not that we can blame the dude.
"Harry [...] I as good as killed them," he croaked. "I persuaded Lily and James to change to Peter at the last moment, persuaded them to use him as their Secret-Keeper instead of me [...] I'm to blame, I know it [...]" (19.72)
Sirius's guilt makes him see himself as something of a bad guy in all of this. His own self-perception, and his willingness to do some bad things, help complicate the ideas of good and evil here. What makes people good or evil in this book? Is it their actions, their ideas, their beliefs, some combination of those things?
"How dare you," he growled, sounding suddenly like the bear-sized dog he had been. "I, a spy for Voldemort? When did I ever sneak around people who were stronger and more powerful than myself?" (19.107)
Sirius delivers a damning judgment against Peter here, as he basically equates Peter's cowardice with evil.
"He – he was taking over everywhere!" gasped Pettigrew. "Wh- what was there to be gained by refusing him?"
"What was there to be gained by fighting the most evil wizard that has ever existed?" said Black, with a terrible fury in his face. "Only innocent lives, Peter!" (19.162-3)
The contrast between the speaking styles of Peter and Sirius is interesting here. Peter stutters and asks desperate questions; Sirius speaks decisively and uses morally-charged words like "evil" and "innocent lives."
"I'm not doing this for you. I'm doing it because – I don't reckon my dad would've wanted them to become killers – just for you." (19.174)
If there's a common thread uniting all the Harry Potter books it's the idea that doing the right thing isn't always easy. Harry arguably does the right thing here by stopping his father's friends from becoming murderers, but it's a hard to not take revenge against Peter.
"Think that matters to [Dementors]? They don' care. Long as they've got a couple o' hundred humans stuck with 'em, so they can leech all the happiness out of 'em, they don't give a damn who's guilty an' who's not." (11.2.87)
Since the Dementors are the epitome of bad in Book 3, it stands to reason that they would not pay attention to pesky distinctions like "guilt" and "innocence."