[akvadrako]

> If a previous administration passed a rule, I don't know what argument we can use to say that a future administration can't change that rule.

This is what's going through the courts now with the DACA program. It isn't a law but something the Obama administration came up with. Up til now the courts have said the current administration doesn't have good enough reasons to rescind it.

So there are a few legal arguments that prevent rule changes.