When you take away the rights of the few, you take away the rights of us all. Mentally ill people need help, not reported to the government! Equalization of treatment is one step in the right direction. Putting more people under the control of any governmental front is NOT.
Do you really think that keeping a registry of say.. people who are depressed.. will stop carnage? No. It will just keep people who need help from getting it, from wanting it, out of fear.