In a nutshell, what happens is Congress makes a law that says "the Secretary shall implement rules". The Secretary will be defined as. for example, the HHS Secretary (remember Kathleen Sebelius?") Then, in addition to a 2000 page law like Obamacare, you have 40,000 pages of implementing "Regulations." The Regulations cannot conflict with the plain language of the statute, but otherwise it's a free for all and executive branch bureaucrats like Sebelius are free to draft any regulation they want, which are really just laws by another name. This is an in your face violation of Article II of the Constitution which specifically says Congress has the exclusive right and duty to "make law." The separation of powers depends on adhering to these delegated roles obviously. We don't elect people like Sebelius and we can't get rid of people like her. Okay, rant over. Has always driven me crazy. Calling them "rules" doesn't change the fact that they are effectively laws. Congress passes the buck to avoid accountability and then people like Pelosi say things like "We have to pass. it first to find out what's in it!" That is Chevron in a nutshell. It NEEDS to be overturned.