Red Flag laws in general. Or at least what Trump and other politicians are calling for.
Trump said:
https://www.whitehouse.gov/briefings-statements/remarks-president-trump-mass-shootings-texas-ohio/
Current laws state that states have to show "clear and convincing evidence" that someone with a menatl illness poses a danger to themselves or others.
Believing in white supremacy, or black supremacy, or other racist ideologies should not be grounds for involuntary confinement.
Unfortunately, Trump's Chief of Staff, Mick Mulvaney, seems to believe otherwise. Highlighting the problem with a government deciding things like this.
https://abcnews.go.com/Politics/week-transcript-19-mick-mulvaney-rep-veronica-escobar/story?id=64764985
It's disheartening that these Constitution-loving people don't understand the 4A protections we, the people, have.
SCOTUS as already ruled that:
https://caselaw.findlaw.com/us-supreme-court/441/418.html
To make things even more complicated, each state differs on what constitutes reasoniong for involuntary confinement.
https://www.treatmentadvocacycenter.org/storage/documents/state-standards/state-standards-for-civil-commitment.pdf
So, when people (i.e. Trump) say we need to "better identify mentally disturbed individuals who may commit acts of violence", hopefully he's not talkign about loosening any sort of restrictions that would cause innocent people to be caught in this dragnet.
From a practical standpoint and from people much smarter than myself,
https://www.nytimes.com/2019/08/05/health/mass-shootings-mental-health.html
https://heinonline.org/HOL/LandingPage?handle=hein.journals/hastlj55&div=3&id=&page=
More to the point, psychiatrists are notoriously bad at predicting individuals' predication for gun violence.
https://caselaw.findlaw.com/us-supreme-court/463/880.html