#1: Your plot, as it stands, hinges on the idea of magical Britain being bound by a Wizard's Charter. There is no Wizard's Charter ever mentioned in any of the Harry Potter novels; the closest I can find is the Wizengamot Charter of Rights mentioned in OotP. Your plot also says that this Wizard's Charter obliges the magical community to uphold the British Constitution. The UK doesn't have a written Constitution to uphold.

#2: Again, Sirius never called Harry "pup" in the books, at least as far as I can tell. If memory serves, he occasionally addresses Harry as Prongslet, but I can't remember off the top of my head.

#3: The Magna Carta is an 800-year-old document that had been entirely superseded even by the dates you set for your Wizard's Charter. If you're having Harry entreat the Queen for assistance, you've got to do it with reference to modern law, rather than something so ancient it's basically written in a different language.

I trust this expresses my issues more clearly and with some measure of wit. =]

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"She's old, she's lame, she's barren too, // "She's not worth feed or hay, // "But I'll give her this," - he blew smoke at me - // "She was something in her day." -- Garnet Rogers, Small Victory

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