Whys is Snape allowed to continue spying?

[jenzajlp]

No: HPFGUIDX 131521

Chris wrote:
Perhaps this has been discussed, I'm not sure. During my re-reads a 
question has popped into my mind. Why is Snape allowed to continue to 
get close to Death Eaters like Malfoy? Voldemort obviously knows that 
Snape has betrayed him and joined the Order. Luicius Malfoy more than 
likely knows that Snape is a traitor by now? How can he continue in 
his function as spy when everyone knows he has joined DD. Or am I 
missing something?

Jen writes:
Has it actually been confirmed in canon that Snape's job in the Order 
is to spy on the Death Eaters?  It's assumed that this is what he's 
doing by H, Hr, & R, but JKR has been very coy about this subject in 
the books.  At the end of GoF (and please forgive my lack of clear 
references, as I don't have my books in front of me) when Dumbledore 
begins handing out assignements to the professors, he asks Snape if 
he "knows what he must do" (approximate quote).  It is never said 
what Snape is actually doing.  The only other clear reference to 
Snape's duty for the Order is when Harry is practicing Occlumency.  

"...it is not up to you to find out what the Dark Lord is saying to 
his Death Eaters.
'No - that's your job, isn't it?" Harry shot at him.
......
"Yes, Potter...."
(quotes from OotP stolen from Saraquel's post)

IIRC, Snape pauses for a moment before his "Yes, Potter" and smirks 
as he answers.  This passage has always bothered me - Would Snape 
willingly agree with Harry about this if it was the truth?  And if he 
were to confirm this for Harry, would he do it in such a 
smug/condescending way? (Granted, Snape reeks of smug attitude, but 
usually when he's got the upper hand).  If Harry were right about 
this, wouldn't it have caught Snape off guard?  

I read this passage in a different way.  IMO, Harry assumes he knows 
what Snape's job is...but he's wrong. Snape is amused by what he sees 
as Harry's arrogance and smugly agrees, instead of clarifying what 
he's actually doing for the Order.  

Is there anything in canon that specifically says that Snape is 
currently working as a spy?  

I personally think there's something more to Snape's duties than we 
know and that there's a big reason they've been kept a secret from 
us.  Of course...I have no theories on what he could be doing if he's 
not a spy.  Any takers?  :)

Jenza