The Marauder's Map & Pettigrew

[arcum42]

No: HPFGUIDX 45131

--- In HPforGrownups at y..., "corinthum" <kkearney at s...> wrote:
> Arcum suggested:
> 
> > > Or perhaps the map only shows Maurauders to other Maurauders. 
> > Lupin is the only one who saw Sirius or Peter on the map, after
all. 
> > It could have been a safeguard, in case the wrong people got
ahold 
> > of it while it was active...
> 
> And Marina countered:
> 
> > I'm afraid that won't work -- Snape saw Lupin on the map (PoA, US 
> > paperback, pg 358).  That's how he knew to go to the Shrieking 
> Shack.
> 
> 
> Now me:
> 
> That doesn't completely rule out a safety mechanism.  Perhaps there
is 
> some addition spell needed in order to make the map show the 
> marauders.  Snape didn't activate the map at all; Lupin did.  So
it's 
> possible Lupin performed this additional spell that night.  Why, of 
> course, I wouldn't know.  Perhaps he was checking to make sure
Sirius 
> hadn't payed another unexpected visit, or maybe it was simply force
of 
> habit.
> 
Along the same lines, it could be that "I solomnly swear I am up to
no good" is a general activation code anyone the map trusts can use,
with a "guest" mode, and that each of the marauders had a different
code, which would fully activate it.

It could even be slightly subler, with the "guest code" Harry and Co
know not showing any of the Marauders *in animagus form*, and Lupins
code showing everything. After all, the Marauders didn't want their
animagus forms as general knowledge, and may have wanted to be able
to demonstrate the map without giving themselves away.

Under this theory, Lupin used his code because it is the one he
standardly uses, and Snape only saw Lupin on the map because he was
careless enough to leave it activated on his desk. In a hurry or not,
couldn't Lupin have said "Mischief Managed!" before leaving his desk?
Makes you wonder if similar carelessness got it confiscated
originally...

--Arcum