'chained these 12 years..'

[pippin_999]

Talisman: 
> You may have noticed how easy it was for DD to absolve Sirius, after 
> Sirius's death.  This, though there was no body, and there were no 
> witnesses save some DEs, who had their own reasons for killing the 
> putative Potter SK/erstwhile Voldemortian spy.

Pippin:
Aren't you forgetting all the other Order Members? Shacklebolt,
Moody, Tonks and Lupin could all testify that Sirius was fighting on
their side, not Voldemort's, and Shacklebolt and Tonks, at least
were considered highly  reliable Ministry employees. Also, that
Sirius had been at Grimmauld Place all along and could not have
helped Bella and the others escape from Azkaban.

Talisman:
> This is exactly the way DD springs Hagrid from Azkaban in CoS: by 
> *jotting up a little note*--with no other evidence at all.

Pippin:
The evidence is that Ginny was attacked and taken into the chamber
while Hagrid was safely in Azkaban.

Talisman:

> When DD said, after, that Sirius's death was his (DD's) fault, he 
> wasn't kidding.

Pippin:
It was his fault for giving Lupin a third chance. 

Pippin
Who thinks the karmic aspect to Sirius's death was that he
never could bring himself to tell DD why he'd  suspected Lupin