What did Snape know, and When did he know it?

[pippin_999]

No: HPFGUIDX 169390

:
>
> Mike:
> I was going to respond point by point, but that didn't work so well 
> last time. So instead, let me lay out my theoretical timeline and you 
> all can point out where I'm off base. :)
> 
> 1) Peter Pettigrew starts spying for Voldemort.

> There are a fair few true DEs that know that Severus Snape is spying 
> for Voldemort. I gotta believe that although Voldie would hold 
> Peter's allegiance close to the vest, he would tell someone. 
> Pettigrew would have a handler, a middleman who took Peter's info to 
> LV. And he probably told more than just that one. He wouldn't want to 
> have to handle Peter personally all the time.

Pippin:
As Snape is at Hogwarts, he would not be in a convenient position
to handle Peter. Peter can travel anywhere in his rat disguise, but
why make him go all the way to Hogwarts? Order HQ was doubtless
in London then as now, because the target they are trying to 
protect is the Ministry. The spy's handlers will be in London too.

I suggest some additional steps. 

1.1  Snape discovers that Voldemort has an informant code
named 'Wormtail' and reveals this to Dumbledore, along with
the information that  Wormtail was the school nickname of 
Peter Pettigrew.  The identity of the informant is kept very secret.
As we know, wizards have better ways that robes and masks to
conceal their appearance, and these would certainly be used. 
Dumbledore considers him to be a powerful wizard who 
acted as Voldemort's second in command, as Fudge reports in PoA. 
It would seem obvious that it cannot be Peter Pettigrew.


1.2 Since Snape is not supposed to have revealed the 
Wormtail code name, Dumbledore will not let anyone 
know that he knows it. He interrogates the 
Potters' close friends, and it becomes clear that he thinks
that someone close to them must be the spy. 

1.3 Pettigrew is not found out, either because,
contrary to all appearances, he is a superb occlumens, or because,
contrary to all later appearances, he is not the spy. 
The real spy must be a superb occlumens of course. 

Mike:
> 2) Dumbledore suggests the Fidelius to the Potters. They tell DD they 
> are going to use Black, then switch at the last minute to Pettigrew.
> I would think that DD would have told Snape about the Fidelius and 
> that Black was going to be the SK. If for no other reason than Snape 
> would have the same plausible deniability that he had with Bella in 
> Spinner's End. To wit: I can't tell you where the Potters are, they 
> are under the Fidelius Charm. And why would DD hide his understanding 
> that Black was the SK? Besides, it seems to have become a known fact.

Pippin:
Not known to very many, according to Fudge. Most people think
that Black's crime was the murder of twelve Muggles and a wizard. 
Most people have never even heard of the secret keeper spell.

2.1 Snape, thinking that  Sirius is the spy, breaks cover and 
warns the Potters not to use Sirius as their Secret Keeper. 
James will not listen to his warnings.

<snip> points 3-6 which I agree with

Mike:
> 7) The in-the-know DEs start spreading it around that PP was the 
> Potter's SK and led LV to the Potters, whereupon he vanished.
> As I explained previously, these few in-the-know DEs don't want to 
> take the fall for LV's demise.

Pippin:
Um, why would they? Only the secret keeper can have
betrayed the secret. Unless these individuals were known friends
of the Potters, they can't have been the secret keeper, so what
have they to fear? The only reason Peter's handler would have to
be afraid is if he were known to be a friend of the Potter's or
a friend of Dumbledore's as well.

But of course if he were a friend of the Potters, he would want
those voices silenced. How fortunate for him that everyone who
knows that Wormtail was the secret keeper and is willing to 
talk about it ends up in Azkaban. It would have been hard for
Peter Pettigrew to arrange this, since he was busy pretending
to be dead. But we don't know what Remus was doing, do we?

Mike:
> 8) Snape learns this info about PP in due course and reports it to 
> Dumbledore.

Pippin:
Snape  would not learn anything more, since Lucius is pretending
he was under the Imperius Curse and has no contact with
anyone thought to be a faithful DE. Snape wants to believe
Lucius, his old protector, thus the sudden movement when
Harry reveals that Lucius was at the graveyard.

Dumbledore knows that Wormtail was the spy, but he thinks
that Sirius Black was 'Wormtail'. Dumbledore does not press 
for a trial of Sirius because he knows there isn't  enough 
evidence to overturn the verdict. 

If Sirius is guilty, he is where he belongs. If he is innocent,
then evidence will appear in due course, and it will be easier
to free him if his conviction is not in order.

Black is in Azkaban, James is dead, and where, pray tell, is Remus?
JKR doesn't want us to know. That is the single most 
suspicious circumstance in the whole saga, IMO. 
Did Sirius and James ever share their suspicion of Remus
with Dumbledore? Did Dumbledore refuse to believe them
because of his emotional investment in Lupin?

It is hardly outrageous for Snape to have suspected Sirius
and Lupin of being spies, since they even suspected each other.
Sirius's suspicions of Lupin cannot have been based on 
Lupin's lycanthropy. There must have been other evidence.
Nor would Sirius's conviction necessarily clear Lupin --
as you say, spies seldom work alone. 

Snape, listening under the cloak, hears Lupin tell the
story of the prank, and it turns out that James was *not*
in on it. But that means that James committed a very
serious offense by going to rescue Snape -- he ratted
out his friends and exposed them to the dangers of
being expelled. It would be no wonder if Lupin and
Sirius never quite forgave James for that. 

In fact that gives Snape a motive to think that Lupin and
Sirius might have turned against James, doesn't it? James
had violated the code. 

Pippin