Don't the Death Eaters know that Snape's a spy?

[huntergreen_3]

No: HPFGUIDX 106643

Jenn wrote:
>>> At the end of Goblet of Fire, Voldemort summons the Death Eaters.
They form a circle, and, while he doesn't mention him by name,
Voldemort indicates that one of the six who are missing has left him
forever and will, of course, be killed. Wouldn't Voldemort have
told the remaining Death Eaters who it is who has left his service
forever? Why hasn't an attempt been made on Snape's life? <<<

Sen replied:
>> It seems to me as if Snape & Malfoy are still kind of chummy to 
some degree (whether it's real or a front). I mean, how else would 
Snape know Lucius recognized him? 

[snip] I wondered if somehow Snape was *not* one of the 3 DE's 
Voldemort mentions in his GoF speech. <<

HunterGreen:
This has been debated back and forth many times, and many theories 
have been thrown around as to who those two death eaters are. 
Personally, I've always had same belief since I read GoF the first 
time. Snape is 'the one who left forever'. Why shouldn't it be the 
obvious answer in this case? There's been nothing really to refute 
that. As proof I offer all the hints that Snape is now spying on the 
DE's (the request he makes on Snape at the end of GoF, and Snape's 
non-denial of this fact when Harry says it during the Occulmency 
lessons). Of course, this is not absolute proof, but its all 
speculation anyway.
This begs a question though: How did Snape get back into the fold 
when Voldemort believes he left forever and is planning to kill him? 
Its always seemed rather simple, Snape appeared later that night (the 
dark mark must be some sort of homing mechanism, perhaps it was still 
strong enough for Snape to find him hours later), and explained 
himself. Voldemort's remark about Snape always seemed less angry than 
the one about the one 'too cowardly to return', (about that, I wonder 
if he did something that was the reason Snape turned his back on the 
DEs, and Voldemort is not surprised that he left) thus it seems 
reasonable that Snape had at least a shot at getting himself back 
into the DE circle. 
For one thing, Snape certainly was not in a position to just take off 
out of the school and run off to a Death Eater meeting when the dark 
mark appeared, and Voldemort knew that. Barty Jr. isn't there either 
for the same reason. Another thing is that its very helpful for 
Voldemort to have a DE in Hogwarts, keeping an eye on Dumbledore. He 
may have tortured Snape, or demanded something of him (perhaps using 
Legimency? which we all know wouldn't matter with Snape).

As for Snape's relationship with Lucius and Draco, I don't there's 
anything fake about it. I think despite his position as a spy, Snape 
is still (and has been) friends with Lucius. There's a good chance 
that Lucius was a member of that "Slytherin gang" Snape was said to 
have belonged to (and being several years older, he may have been a 
menter figure for Snape; in fact according to Sirius he was 
Lucius' "lapdog", which may be a reference to some sort of adulation 
on Snape's part). Lucius also appears to like Snape as well. 
According to Umbridge (don't know the chapter number offand, but it 
was toward to end of the book), Lucius speaks quite highly of Snape.