The usual way. It's not hard.
Oh do explain, since it's so easy.
A regular jail, where they have access to a lawyer and the other protections of due process enshrined in our most fundamental laws.
But I thought America's prison system was broken too?
No one is saying for criminals to do whatever they want. We just want you lot to acknowledge that the law of the land ensures due process to everyone, not just citizens.
Finally you say something we can all agree upon.
Your analogy isn't applicable.
Because you don't want it to be... Sure it isn't applicable to every single situation, but I'd be willing to guess it applies to a majority.
These people aren't being arrested mid-crime, they're kidnapping them from their homes, off the street, at their jobs, and again, at their legal immigration hearings.
Isn't being in a country when you're not supposed to be "mid-crime"?
And as much as you clearly want it to be "kidnapping", it's not. It's called "unlawful arrest" or "wrongful arrest", and a quick Google search shows these people are about to get a large settlement.
Again, it's not perfect, but nothing is. All I can hope is that the actual victims are compensated handsomely.