Through delegated lawmaking. When agencies overstep those boundaries, the courts have been more than happy to strike them down.

And to be fair, my statement should have included the executive. It should not include the judiciary, who have a more limited--albeit equally powerful--role in our government.

We could argue about scope, but we can’t really argue about whether the power exists. And that’s to say nothing of SCOTUS, which gets to interpret complex notions like “freedom”, “liberty”, “search”, “privacy” and so forth as used in the constitution, laws passed by congress, etc.