Hagrid’s sobs redoubled, but he shoved the letter toward Harry, who Picked it up and read aloud: Dear Mr. Hagrid, Further to our inquiry into the attack by a hippogriff on a student in your class, we have accepted the assurances of Professor Dumbledore that you bear no responsibility for the regrettable incident.
There are no more uses of "inquiry" in the book.
Show samples from other sources
They created a commission of inquiry to look into the matter.
The official inquiry has ended, but the press continues to ask questions.