the behind-the-scenes balance of power having drastically shifted (though the death makes a nice pretext) and about the threats and concessions we haven't seen yet making it possible.

Remember that everyone saw Harry threaten a Dementor.

There are a certain few of the Wizengamot who have read through half-disintegrated scrolls and listened to tales of things that happened to someone's brother's cousin, not for entertainment, but as part of a quest for power and truth. They have already marked the Night of Godric's Hollow, as reported by Albus Dumbledore, as an anomalous and potentially important event. They have wondered why it happened, if it did happen; or if not, why Dumbledore is lying.

And when an eleven-year-old boy rises up and says "Lucius Malfoy" in that cold adult voice, and goes on to speak words one simply would not expect to hear from a first-year in Hogwarts, they do not allow the fact to slip into the lawless blurs of legends and the premises of plays.

They mark it as a clue.

They add it to the list.

This list is beginning to look somewhat alarming.

My guess is that those in power who noticed all this are trying to ally themselves with this powerful new piece on the gameboard, and used their sway to get people to agree to it.