My own take on the Prank

[zanooda2]

No: HPFGUIDX 152630

> Steve:

< almost everything snipped>

> Final note, again based in speculation, I think it is unfathomable to
> think that no one was punished. That seems completely unlikely and
> unreasonable even from wizard world perspective. I suspect everyone
> including Snape was punished severly, but punished in the framework of
> school. In otherwords, a long series of unpleasant detentions and
> docking of house points. And, given that no one was hurt, that seems
> appropriate.


Of course they were punished. As for expulsions, they seem to be much
harsher punishment in WW than in RW. If you are expelled, you  not
only cannot continue your education, but your wand is taken away and
broken (remember Hagrid). You are forbidden to do magic and are
reduced to a Squib existence for the rest of your life (correct me if
I'm wrong).
 
That's why probably this punishment is reserved for extreme cases,
like actual murder. The only expulsion that we even know of is
Hagrid's, who was accused (falsely) of murder. Harry was not expelled
for using Sectumsempra, even though it is potentially murderous curse.
If Snape didn't happen to be there, Malfoy could have bled to death.

Harry didn't know what this spell did, but he could have hard time
proving it. By the way, I always wondered why don't they teach Latin
in Hogwarts? Most of the spells are based on Latin, and, if Harry knew
it, he could have guessed what the words levicorpus and sectumsempra
mean.I know I guessed, and I studied Latin very briefly and 25 years ago.

 zanooda