Who cast the Fidelius on James and Lily?

[KathyK]

No: HPFGUIDX 127613


Amiable Dorsai:
 
> I've long been under the impression that Dumbledore cast the 
> Fidelius Charm that was supposed to hide the Potters at Godric's
> Hollow, but I can't find any reference to that after a quick
perusal 
> of PoA.  I ask because it seems odd to me that if Dumbledore cast
the
> spell, he wouldn't know who the Secret Keeper was.  (Although, I 
> suppose that knowledge of who the SK is could be one of the things
> hidden by the charm).
 
KathyK:

You're right.  We don't get the direct answer as to who cast the 
Fidelius Charm over the Potters.   I think for the most part when 
discussing this I have assumed that Lily did the casting, glossing 
over the whole question in favour of other burning Secret-Keeping 
issues.  Based solely on the flimsy evidence from Ollivander in PS/SS 
that Lily's wand was good for Charm work, I concluded that it made 
sense for her to be the one who did it.  

But you could have something there.  Perhaps once the spell is cast 
the knowledge of who is SK can be hidden as well.  I wonder how that 
might work, though.  Another one of my assumptions is that the 
Fidelius Charm must be performed with those involved present.  
Meaning, when the charm was sealed, James, Lily, and Peter were 
there.  If the SK's identity was also hidden by the spell, would the 
person performing the spell afterward stand there wondering why they 
were all there?  Or perhaps it's merely a matter of a well-placed
(and 
in this sort of case, preferably consentual) Obliviate, and all is 
safe.  

If it wasn't Lily or Dumbledore, perhaps Flitwick had a hand?  Or 
perhaps Sirius?  He certainly knew the identity of the Secret-Keeper.
 
Maybe he was there to cast the charm.  I would rather the Charm be 
performed by one of the folks in the know (Sirius, Lily, James, 
Peter).  It's the simplest explanation.  No need to complicate the 
Fidelius Charm mystery further.  

KathyK, who has quite a Secret-Keeping Obsession but hasn't played 
with it in a while