Well, from my 6 years experience as a teacher administering standardized exams, I’ve never seen a state rep. at a test, but the admin. have always said that they “could” come.
The point where this stuff happens is in the classroom (teachers pointing at answers, nodding, shaking heads), and when the tests get put in the vault (they get taken out and erased - but this can be found out by erasure analysis).
Any teacher and or administrator caught doing this should be immediately fired and lose their pension. Any school where this is widespread should be closed immediately with all the teachers and administrators fired.
I think they should be prosecuted for fraud too.
One solution might be to bar any teacher from proctoring the testing of her own students. On test day, the teachers get put on buses and randomly sent to schools in neighboring school districts, with assignment made on testing day to preclude making quick deals with known counterparts.