Why did Sirius trust Pettigrew? WAS: Snape investigating Potters' Betrayal

[Frank D]

No: HPFGUIDX 186548

Frank D: 
This may be old stuff to most on this list, but I am constantly being reminded of how ignorant I am about this subject. Please excuse me if this has been discussed and put to rest before.

I'm at a loss to answer this question with any degree of confidence: Why was such "blind" trust in Peter Pettigrew so firm among James/Sirius/Lupin? Especially since Pettigrew eventually proved to be such a weakling and (so obviously) a RAT? It just doesn't seem plausible to me that a person with such character faults could have been trusted so fully by James and Sirius. And shouldn't Lily have had some say in the decisions about who would be their life-protecting Secret Keeper?

A little background:

--- In HPforGrownups at yahoogroups.com, "Carol" <justcarol67 at ...> wrote:
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> Carol again:
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>. . . it *is* a fact (within canon) that Snape thinks Black entered the castle to murder Harry and that Lupin has been helping him all year. That assumption (also made by Dumbledore, Fudge, Mr. Weasley, and everyone else except Sirius Black himself and Pettigrew) would naturally strengthen Snape's view that Black betrayed the Potters to their deaths. 
> 
<snip>
> . . . Snape [has] every reason to believe that Sirius Black betrayed the Potters and no reason to think otherwise . . . 
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<snip>
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>But Dumbledore's efforts to protect Lily (and, of course, James and Harry) were in vain because James Potter trusted Sirius Black and made him the Secret Keeper. That, IMO, is why Snape is so furious at Black and the dead James--if it weren't for James Potter's blind trust in his friend, Lily would still be alive. (In DH, Dumbledore reinforces this belief, saying to the desperately grieving young Snape, "She {Lily] and James put their faith in the wrong person" and comparing their faith in their unworthy Secret Keeper to his own hope that Voldemort would spare Lily (DH Am. ed. 678), a comparison that Snape seems to hear only half of given his subsequent virulent hatred of the man he thinks is Lily's betrayer. In a way, he's right, but, of course, the friend that James trusted was Peter Pettigrew, not Black.
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Frank D again:
Here is a bit of what I found on searching the list's history:

>Jan 28, 2008 8:37 pm
>Message #181103

Julie wrote: 
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<snip>
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>Given that Sirius treated Ratboy as little more than a sycophantic hanger-on who was lesser in every way than the other three, how could he NOT have suspected such lesser makeup might have included character and courage?
>
>Or at least that Ratboy might have some resentment issues over being
constantly reflected in the limelight of the Golden Duo throughout all their schooldays.
>
>As part of said Golden Duo, [James] was pretty dim too. And who in their right mind would refuse *Dumbledore*--one of the greatest
Wizards who ever lived--as Secret-Keeper, then hand the lives of his family over to reasonably competent at best Ratboy?

>Truly there should have been more to this whole story than what we got, including why James refused Dumbledore, what Dumbledore knew and why he let Snape go without obliviating him, why Sirius suspected Lupin and vice-versa, etc. But JKR didn't give it to us, so we can only work with what is there. And with our individual opinions and valuations of course ;-)

>Julie

Any help toward understanding this would be appreciated.

Frank D