Long ago, in the founding of Equestria, before the Two Sisters and the Pillars, Ponykind developed laws and punishment for those who broke said laws. They established order in the chaos. Even today, under Twilight Sparkle's rulership, those laws are still active and binding to keep that order and peace. Twilight Sparkle was not ready to uphold some of them, and neither was she ready to handle the ensuing fallout that was thrust upon not just Equestria, but the entire world.

Rainbow Dash faces lady justice for everything she did and Twilight Sparkle's status as Princess of Equestria is not above the law.

Author's note: This is an uncharacteristic story for me. Still today, hanging is a common method of execution. I accidentally asked the question, how would you hang a Pegasus for high treason?