Perhaps casting Imperius is detected by Hogwarts wards. This is in fact more likely (that is, it better fits my impression of what wards should be like) than supposing that Hogwarts wards detect ongoing Imperius enchantments.
‘ongoing’ doesn’t seem to be the germane distinction. For example, in canon book 7, don’t the Gringotts wards and mechanisms detect both ongoing polymorph and an Imperius when Harry et al break in?
Goblins have a history of taking certain things very seriously, and security is one of them. The Ministry is very serious about looking like they take security seriously. The difference is not a small one.
Perhaps casting Imperius is detected by Hogwarts wards. This is in fact more likely (that is, it better fits my impression of what wards should be like) than supposing that Hogwarts wards detect ongoing Imperius enchantments.
‘ongoing’ doesn’t seem to be the germane distinction. For example, in canon book 7, don’t the Gringotts wards and mechanisms detect both ongoing polymorph and an Imperius when Harry et al break in?
No, the Imperius was cast inside the bank.
If that were valid here, then wouldn’t Gringotts be the place to send Ministry employees at random thrice a week?
Yup. Why does Gringotts have better and useful wards than the Ministry? Because they’re all idiots.
Goblins have a history of taking certain things very seriously, and security is one of them. The Ministry is very serious about looking like they take security seriously. The difference is not a small one.