This is an interesting article that states since Alvaro Castillo voluntarily admitted himself to a mental hospital that he was still allowed to purchase firearms…
HILLSBOROUGH, N.C. – A teen jailed on charges he fatally shot his father before opening fire at his former high school was able to buy two guns even though he was nearly involuntarily committed to a mental hospital just months earlier because of his suicide threats.
Instead, Alvaro Castillo agreed after the involuntary commitment process had started to admit himself to the hospital. That allowed him to retain his right to buy a gun.
For nearly 40 years, federal law has made it illegal to knowingly sell guns to a person who has been involuntarily committed to a mental institution or otherwise been found by a judge to be mentally ill.
The difference between those who get involuntary and voluntary treatment often is small, but it can have potentially huge consequences, said Mark Botts, a law professor at the University of North Carolina at Chapel Hill School of Government.
North Carolina law encourages authorities to persuade a person to consent to treatment even when the person is considered dangerous and eligible for involuntary treatment.
But when consent is given, the state no longer has control over the duration of the person’s treatment because willing patients are allowed to voluntarily discharge themselves, Botts said.
In case you forgot Alvaro Castillo shot and killed his father before opening fire on his former high school.