This isn't a "get rid of pervy teachers" move (though that is certainly a justification that is given). If it was, there would be measures put in place to make sure they were only targeting the pervy teachers. Instead, this is all focused on test scores. Test scores (and whether students improve on them past a set mark) don't correlate to whether a teacher is a perv.
Instead, the real reason behind this attack is two-fold. First of all, the teachers' union didn't support Andrew Cuomo in his re-election campaign. So this is political retaliation. Secondly, Cuomo is a big fan of business-run Charter schools and has said that he would love to replace public schools with charter schools. In fact, part of his recent "reforms package" was that a school deemed under-performing would be placed into receivership. The third party receiver could turn the school into a charter school and fire all of the teachers/administrators regardless of any tenure. (This is happening in my son's school.)
Most of this is tied to the high stakes tests which Cuomo said students shouldn't feel anxious over because the tests don't matter for the students. How much incentive do you think kids will have to do well on a test that doesn't affect them directly?
The whole system has been designed to punish public school teachers for the sole reason of punishing public school teachers. If Cuomo has his way, don't be surprised if - in 5 years - we have no more public schools and only have business-run, for-profit charter schools.