So, I figure this is something the dark lord would use, and the dark side in general. By using the Imperius curse on someone who worked for the enemy, one could gather information by forcing this someone to be a spy.
However, there is never mention of the MoM using techniques like this in the books (or extra-content that I've seen). They are, however, known to use the killing curse in situations of war, and great danger (specially among the aurors). So that begs the question:
Do they ever use the Imperius curse as a way to force an enemy's "soldier" to spy for them?
P.S.: If you question the morals of using the Imperius curse, well, using the killing curse is much worse, not to mention that by using the Imperius curse they could keep their own man and woman from getting into danger. Besides,
governments have no morals using an enemy as a spy makes it much easier to convince the enemies that they are not.