Madam Bones, Head of the Department of Magical Law Enforcement, was summoned along with Aurors Kingsley Shacklebolt and Hestia Jones to Professor Dumbledore's office. Dumbledore had Floo'd Madam Bones with the report of an Animagus being caught while living in the boys dorms in Gryffindor Tower. Few things motivate LEO's anywhere like the chance to arrest a sexual predator that preys on children.
Madam Bones arrived to find Dumbledore along with a red-haired boy that could only be one or Arthur's sons and a girl the same age with thick, impossibly bushy hair. Based on Susan's reports of school she deduced the girl must be Hermione Granger. Bound in a chair in front of them was a short balding man; a little stout and very slovenly looking.
"What do we have here, Albus?"
"Mr Weasley and Ms Granger came to me tonight with this man and a most extraordinary story."
"He's my rat, Scabbers," Ron burst out. "The creepy git's been sleeping in my bed for years. And before that he was my brother Percy's."
"Ron!" the girl hissed. Then she turned to the DMLE Head. "Hello Madam Bones. I am Hermione Granger. I was doing some reading about Animagi and I came across a spell to identify an animagus in their animal form. I wanted to try to cast it for myself. I was more than a bit surprised when it caused Scabber's to glow. Fortunately he was asleep and I had a bit of time to do some more research. I found the spell to force an animagus back into human form. That is when this man appeared."
Madam Bones nodded her understanding. She was impressed a Third year in class with her niece could work such obscure magic. It wasn't particularly hard to cast but with so few animagi not many bothered. It was however in keeping with Susan's comments on Ms Granger's personality.
"We don't have any rat animagus listed in the registry," Auror Jones commented.
"The last one was Adam Budd who died in 1803," Ms Granger supplier. Then she blushed when the three Aurors turned to look at her in surprise. "Um, we found out Harry's dad was an unregistered stag animagus. So I looked up the registry."
Madam Bones was shocked again. "This would be James Potter, Harry Potter's father?" The two students nodded. The old witch let a small smile escape. "That crafty little bugger. James always thought rules were more guidelines than anything else. He never even mentioned it to me when I was his training officer.
"Now, who do we have here?" she asked turning back to the bound man.
"I believe I can be of some assistance with that," Dumbledore spoke up. "I believe he is a former Hogwarts student, a former Gryffindor even, but one long taken for dead."
Bones looked up at the Headmaster. "And that is?"
"Peter Pettigrew, the man Sirius Black was believed to have murdered after betraying the Potter's to Voldemort. In fact it was his last shouted statement that was seen as key evidence against Black."
The three Aurors looked at the balding man in shock. The possible ramifications of this information were going through each of their heads.
"Right," Bones said. "Kingsley, get back to the office. I want a vial of Veritserium and a deposition quill." Once the Auror was gone she turned to the two students. "And where would Mr Potter be? I understand the three of you are rarely apart."
"He had detention with Snape," Ron provided with a shrug.
"Professor Snape, Ron!" Hermione corrected him. The youngest Weasley male winced slightly.
"Mr Potter was not involved in this discovery so I do not believe his involvement is required at this time," Dumbledore offered.
"Yes, well, the repercussions of tonight if this is indeed Pettigrew will involve Mr Potter," Bones commented. "Now, I don't believe we should keep these students up any longer, do you professor?"
"No, of course." Dumbledore turned and dashed off a quick note that he handed to Hermione. "Please go directly to Gryffindor tower. I shall inform you of what we find out after breakfast tomorrow."
"Yes, professor," Hermione acknowledged. The two students walked out.
After they were gone, Madam Bones asked, "Do you believe all of that?"
Albus chuckled. "For the most part, yes. They may have been a bit hazy with the details and I suspect Mr Potter played a bigger role in this drama than they indicated as I suspect you would agree. But the core story is undeniable. This is indeed Peter Pettigrew. He is missing the finger found at the site of the explosion. I was not Chief Warlock at the time of Sirius Black's arrest but this significantly increases the doubts I've had of Mr Black's guilt."
The conversation was interrupted by the return of Kingsley Shacklebolt with the requested items. Within ten minutes the Headmaster and the law enforcement personnel in the room was appalled at the gross miscarriage of justice that had occurred.