Most  people aren't naive enough to think that this all happened as soon as Berkowitz took over. This is the ripple effect from the giant stone that was dropped into the pond. It took a while for it all to happen, but the waves are here now we are trying to calm them.  Meanwhile the stone thrower walks away and says that the pond was calm when he was there. As far as the academies, they were out of necessity due to the number of officers leaving due to extreme low moral on the department. We reap what we sow, unfortunately most don't see the effects until quite some time later.