*Narcissa laughs mockingly. For all that she doesn't think much of the Weasleys, she thinks far less of Sirius, and directs her rebuttal to the redhaired man.*

On the contrary, Mister Weasley, I've done nothing to prevent any investigation - though perhaps that term can only be loosely applied here. As you can see, the only thing happening here is the systematic destruction of property; I'm sure Minister Crouch will be delighted to hear your explanation for the bill we send.