You can’t have them confiscated without court involvement... Are you claiming that courts are not providing due process?
I hate to break this to you, but you can be involuntary committed temporarily as well... So claiming no due process is a bit of stretch.
When you find systemic abuse, you are going to have an argument to stand on, but given laws like this have existed, that flat out deny people liberty, and have survived constitutional challenges, its hard to see how you are going to win the argument over temporary court based confiscation of a weapon.. that you have the right to contest.
I’m unfamiliar with the process - does the person get a trial if he/she wants or do they just get yanked in and told the weapons are being seized with a judge there to bang a gavel?
How much do you know about the process - a lot I would hope if you’re defending it.