Can a state statute abrogate a federal agency rule that permits non-lawyers to practice before it?

In this scenario, the key principle to understand is the supremacy clause of the U.S. Constitution, which establishes that federal law takes precedence over state law when there is a conflict. Federal agencies have the authority to create rules that govern their procedures and the practice before them, including the standing of non-lawyers to represent individuals or entities.

When a federal agency establishes a rule that allows non-lawyers to practice before it, that rule is authorized by federal statutes and regulations. Therefore, a state statute attempting to abrogate or override this rule would be in direct conflict with federal law. States do not have the power to undermine or negate federal agency rules that fall within the federal agency's jurisdiction.

While there are limited circumstances in which states can impose additional requirements (provided they do not directly conflict) or enact laws that complement federal regulations, they cannot outright disregard a federal rule that has been properly established. Hence, the correct understanding is that a state statute cannot abrogate a federal agency rule, making the answer that states cannot supersede federal regulations accurate.