How Was Harry Potter Not Expelled After Assaulting and Nearly Killing a Student?

Summary:

• In The Half-Blood Prince, Harry’s use of Sectumsempra on Draco almost led to the latter’s death, but Professor Snape didn’t report Harry for it.
• Even a semi-official investigation would have discovered Draco’s use of an Unforgivable curse and his Dark Mark, leading to his trip to Azkaban.
• Severus Snape was bound by an Unbreakable Vow, so if he allowed that to happen, he would have died for letting Draco Malfoy down.

In Harry Potter and the Half-Blood Prince, Harry hits Draco Malfoy with the good old Sectumsempra, and the latter almost bleeds out on the bathroom floor. Fortunately, Professor Snape happens to be nearby and saves the boy’s life; but why doesn’t Snape report Harry to the Headmaster for what looks like an attempted murder?

After all, wasn’t Snape the last person who felt excited about Harry Potter escaping the consequences of his actions over and over again? Why’d he miss his chance?

Snape Couldn’t Say a Word to Anyone

The answer to this question should become obvious if you remember the context of Harry and Draco’s unfortunate encounter. It happened when Draco was already a Death Eater tasked with killing Albus Dumbledore; when Severus Snape was already tied by the Unbreakable Vow to his mother; and when Draco first tried to use the Cruciatus Curse on Harry.

Combined, these facts give a peculiar effect: they prevent Professor Snape from ever talking about the bathroom duel with anyone but maybe Dumbledore. Why?

If Snape tried to officially punish Harry for using a potentially deadly spell on a fellow student, the investigation using Priori Incantatem would have immediately uncovered Draco’s use of an Unforgivable curse; and a mundane medical examination would have revealed his Dark Mark. Draco would have gone to Azkaban in no time.

And Snape, bound by his Vow to Narcissa, would have simply died by failing him.

Harry Would’ve Been Fine Either Way

Even if Severus Snape wasn’t terrified of revealing Draco’s secrets and consequently suffering the unfortunate condition of magic-induced death, there was next to no chance Harry would have gotten punished for using Sectumsempra on Draco in any meaningful way. No, not because of Dumbledore’s favoritism!

The same old Priori Incantatem would have still revealed that Harry acted in self-defense, so no assault or attempted murder charges. And if the investigation looked into the nature of the curse used by Harry, they would have discovered that it was Professor Snape that Harry indirectly learned it from, making him the one responsible as an adult “teaching” dangerous spell incantations to his students.

The entire context of the situation had Harry covered on all flanks, so don’t blame good old Dumbledore for playing favorites with the Chosen One… This time, at least.