This confusion is why to the utmost any type of additional restrictions against the mentally ill should be fought tooth and nail.
Also there will be many gun owners who out of fear of losing their guns or the ability to buy them will not seek treatment for a severe mental illness. The reality that they may be placed in a database that would forever mark them as if they were convicted felons is quite an intimidating fear.
Most mental illness is treatable and the patients can resume a normal life as long as they take their meds. A person that at one time may be a danger to himself or others is not necessarily one that will be for the rest of their lives.
If knowledgable laymen cannot decide what constitutes a predatory or malisciously bent mental illness, how can a lawmaker?