That law was passed during the Kennedy Administration. It took a couple of decades to close them all. You can see older movies of how mental patients were treated although it changed and became more humane. The fact is keeping mental patients in hospital setting is expensive. To do it on a cheaper way may be possible, but then would that be just warehousing them? Many patients personalities fluctuate. Violent ones may not be that way all the time. The Portland political system though has not helped this with its leniency.They sure don't. And the fed pulled its funding for mental hospitals. So, when you see a bunch of homeless people, you can call it the Reagan Project.