Draco, Luna, Pansy, a Slytherin girl (Daphne Greengrass maybe?), Ginny, Umbridge, Harry, Goyle, Ron, Hermione, Milicent, Neville, Crabbe and Snape in J.K. Rowling's Harry Potter and the order of the phoenix
The unnamed girl holding Ginny need not have been a Slytherin. Surely SOME members of other Houses joined the Inquisitorial Squad. Perhaps some Hufflepuffs who felt more loyalty to the Ministry than to Dumbledore, or Gryffindors who, like the Marauders, enjoyed bullying.