Do you think Snape's behavior toward students hurt his abilities as a spy?
Some people believe that Snape's behavior toward his students negatively impacted his abilities as a spy. Do you agree? Why or why not?
I don't think there would have been any difference. Snape was a good spy either way you put it because he knew his reasons for fighting and doing what he did and he stuck to them.
If anything, he sold it off as more believable (especially to Voldemort) because everyone already expect him to be tough with the students, but secretly, he was always trying to protect them.
Yeah, agreed @timeladyjamie.
For being a good spy, Snape needed to have the trust of leaders of both sides and he did. Dumbledore's trust based on his remorse and other Order members trust on the word of Dumbledore assured Snape of Order's trust. He instantly gained Voldemort's trust after his resurrection and most of the Death Eaters trusted him based on it with exception of Bellatrix who was more jealous of it.
Severus was a good spy because he was naturally talented at it. Unlike Barty Crouch Jr., who only spied for one year, Severus spied for 17 years, and his natural demeanor ensured everyone of his supposed loyalties.
Crouch Jr. slipped after Harry returned from the graveyard, but Severus's true loyalties were revealed only after Harry saw fit to voice them after Severus's death.
Severus's favoritism towards Slytherin, his hatred of other houses, his loathing of Harry, his behavior and attitude were all genuine. Faking everything would have eventually led to his downfall as everyone slips when they try to fake their basic instincts. The only thing Severus hid was his relationship with Lily and his guilt; the only person who knew the entire truth was Dumbledore, and even he did not know that Severus was still doing it all for Lily, which explains his surprise at the 'Doe' Patronus.
This question plays on a misconception, which is that Severus was excessively harsh/shitty to his students. Many people (on both sides) seem to believe this, but that's fanon, not canon. Yes, he could be rough on specific students (Harry and his immediate friends), but there's no evidence that he treated students as a whole that way. I'd also point out that even with Harry/Harry's friends, Severus's behavior/punishments were relatively mild, especially compared with other teachers (e.g. McGonagall).
This is what people forget. Severus's behavior was normal within the context of that environment. Hogwarts isn't a world of pats on the head and participation trophies (thank god) – it's based on English boarding schools from decades past where strictness and a low tolerance for bullshit were the norm. It's much easier to understand Severus, particularly his behavior as a teacher, when you don't hold him to 2023 real world standards.
So to answer your question, I don't think his behavior toward students had a negative impact on his abilities as a spy because that behavior was normal. He behaved the way a Hogwarts professor would've been expected to behave in most respects, and even with Harry and friends, his behavior would've seemed entirely appropriate from Voldemort's perspective. Let's not forget that Harry was Voldemort's enemy/responsible for his first downfall. As a "loyal Death Eater", Severus would've been expected to be at least somewhat hostile toward him.
Oh, and speaking of misconceptions…
Severus's favoritism towards Slytherin, his hatred of other houses, his loathing of Harry, his behavior and attitude were all genuine.
There's no evidence that he hated other houses. He obviously had issues with specific Gryffindors, but other than that, he actually comes off as less biased toward other houses than many adults in the series.
There's always this argument that if he were a really skilled spy, he would have fooled everyone much better if he had treated his students better.
Maybe that's true but how well is too well? At what point would Voldemort start doubting Snape's true loyalties? Besides, both sides know that Snape only took on the position because he had to, not because he enjoys imparting wisdom onto empty minds. Dumbledore's side believes he took the position to repay the headmaster for keeping him of Azkaban and Voldemort's side believes he's there to gather information on Dumbledore and the boy who lived.
Then there's the actual reason: Rowling wanted us to hate Snape and see him as the bad guy. From the first book, we are made to doubt and dislike him but that didn't work out as planned as a lot of people had figured things out even prior to the last book (just look at all the Severitus fics written shortly after OotP). If you read the books without having been spoiled, it's quite a wild ride. Snape's bad, actually not really, he protects Harry but he's also downright nasty, he used to be a Death Eater but he's a spy now, no one knows why he changed sides, Snape is a murderer and faked his support of the light all along, wait... that's not right, he actually was loyal to Dumbledore and he even loved Lily! It's this weird back and forth and decades after his backstory was revealed, we are still arguing and speculating about him.
And even in his behavior as a teacher you have this back and forth. Is he just ridiculously strict and has no patience for nonsense or is he really biased against these kids? He does protect them, but also openly bullies them in class but as @heatherlly stated, you need to understand that schools in the 90s or even 70s where Rowling took her inspiration from were vastly different from today's experience. Teachers back then did not act like their student's besties.
But again to the spying. Snape can't just play nice with Harry and Neville, two children openly targeted by the Dark Lord or muggleborns like Hermione. On the other hand, Neville is quite useless in potions and a hazard in that particular class and Hermione keeps interrupting the lesson while Harry and Ron are often unattentive and disrespectful. Then there are Snape's personal demons involved, Harry is a living reminder of Snape's greatest regrets in life; if Neville had been chosen, Lily would be alive now; Hermione is a bright and talented muggleborn witch like Lily and another reminder of his lost friend.
Also, given that Voldemort was convinced of Snape's loyalty until the very end and only found out the truth because Harry told him, I think it is safe to say that Snape was a successful spy and his treatment of his students did not have a negative effect on his performance.
I think that, if anything, Snape played his role a bit too well.
After some pondering, I managed to come up with two reasons why one might think that his treating the students better would've helped with his job as a spy, both of which ultimately have the same flaw.
The first is that he didn't have the trust of the Order, and as a double agent that should have been a part of what made him a good spy. We don't actually have a definitive proof that the Order didn't trust him (with the exception of Sirius), but it's not a far-fetched assumption, so I'll explore it anyway because it's fun.
Snape didn't have the trust of the Order. The argument here is that if they'd seen him act like a decent person with the students (assuming they didn't already believe that to be true), they'd have been more inclined to trust him–
[Side note here, if I knew that Snape was a former Death Eater and suddenly saw him act like a loving parent, I'd definitely be more suspicious...]
–But why would their distrust be a problem if he had the trust of the only person that really mattered? Wouldn't his closeness to the Death Eaters only work in the Light's favour since he'd be able to gather more information? Unless Voldemort came to the same conclusion and started questioning Snape's motives as to why he wasn't trying harder to be in the Order's good graces.
Which leads us to the second reason. Snape's questionable treatment of certain students admittedly brings up the question "Why does Dumbledore trust him?" as seen numerous times throughout the series. The problem here is quite literally the same: wouldn't that be suspicious to Voldemort and thus compromise Snape's role as a spy?
The answer is 'No'. Which might seem illogical, but logic is thrown out of the window when we have facts. And the fact is that Voldemort and at least part of his Death Eaters trusted Snape. We see Narcissa believe that he'd be willing to kill the leader of the Light. So evidently the Dark side trusted him well enough. And that's the only thing that really determines his usefulness as a spy.
@salvyus loved your answer! And we do have somewhat proof that the order didn't really trust Snape or rather they only trusted Dumbledore's judgement. After Snape murders Dumbledore, Minerva and Lupin are surprised that Dumbledore could have trusted the wrong person, they are not surprised by what Snape did but by Dumbledore having made such a grave mistake. That's one thing that bothered me in canon and made me pity Snape, no one really knew and trusted him. Dumbledore did but he also just used Snape as a tool and didn't hesitate to set things up in such a way that would end in Snape's death.
