Red Flag Laws are an International Embrassment. I can't find a single example of a red flag law that stopped a would be mass shooter.

In fact, some places where red flag laws were in place failed to stop mass shooters, like the YouTube shooter a few years back. Her family contacted the authorities and said she might do that. They did everything right. The police encountered her and let her go, and she did her shooting at YT HQ. This was a textbook example of when Red Flag Laws should have worked and it failed to stop a shooting.