When did Snape's spying career begin?

[ssk7882]

No: HPFGUIDX 36175

Dicentra asked:

> Somebody check GoF again.  (I've only got PoA with me today.) Does 
> it *say* that Snape was a DE who turned or does it only say that he 
> was a spy?  What if he never was a DE?  That would be interesting.

Cassie replied:

> Well, I think we can be sure that he was a DE. Why? Because he has 
> the Dark Mark burned on his arm. 

He's got the Dark Mark, and from his reaction to Crouch/Moody in
"The Egg and the Eye," he would seem to be deeply ashamed of it.

Also, Dumbledore told the tribunal that he was, in the Pensieve 
chapter.

"I have given evidence already on this matter. . . .Severus Snape
was indeed a Death Eater.  However, he rejoined our side before
Lord Voldemort's downfall and turned spy for us, at great personal
risk.  He is now no more a Death Eater than I am." 

I don't think he was lying (although like Athena, I do often find
myself wondering why he chose announce it to the entire room like 
that).

Yeah.  Snape was a DE, all right.

-- Elkins