Amelia choose to start with Sirius, as that will be the one they will have the least trouble with doing.
Amelia put three drops of Veritaserum on Sirius tongue and Amelia checked that it was working with the questions. " What's your name?"
"Sirius Orion Black." Amelia nodded to show that the serum was working.
"Now Sirius, who was the secret keeper for the Potter house?"
Sirius answered " Peter Pettigrew." Close to everyone gasped when they heard that.
Amelia then asked " Who killed all those muggles?"
" Peter did."
Amelia had already gotten all the answers she wanted so, she said " Now light your wand if you think that Lord Black is gulity."
Harry saw that no one voted for gulity and that made him very happy, that no one were stupid enough to vote gulity.
After seeing that no one lighted their wands Amelia said " Now light your wand if you think that Lord Black is not gulity."
Everyone voted for not gulity.
Amelia smiled a little and said. " Lord Black you're cleared of all charges against you."
Sirius smiled very widely and went up to sit in his chair as Lord Black even when he really didn't want to do that.
Amelia said " Now it's time for the trial of Bellatrix Isabella Lestrange nee Black. Aurors bring her in!"
When the Aurors came with Bellatrix, Harry saw that she looked completely dead almost, like she didn't have any will anymore. Amelia now asked " Aurors, check for any mind potions, please." One of the aurors took their wand and pointed it at Bellatrix and after a few seconds the auror told Amelia. " Lady Lestrange has many loyalty and obedience potions in her head, that makes it impossible for her to fight against what her husband wants her to."
Amelia just nodded at the information and asked the auror to gat veritaserum and get it in Bellatrix body. After that was done Amelia choose to just ask one question and that was. " Bellatrix did you do any crimes willingly during the last 20 years." Bellatrix answered with a no.
Amelia now smiled and said. " Well, that means that Lady Lestrange has done nothing wrong and that means that you Lady Lestrange are free to go."
That made Bellatrix smile and she went up to the entrance of the Wizengamot to leave the buliding. Harry had a sad look watching Bellatrix leave on the outside, but on the inside he was very happy, due to the first part of his plan going of without any problems.
A/N: Do not expect a chapter before after new years, due to school being hectic. Also in my canon, to make veritaserum work you need to speak the name of the person you want the truth out of.