Today, the Supreme Court decided to review the case of Department of Justice v. McNutt, which challenges a federal law banning home distilleries. The key question in the case is whether the law in question is justified by the combination of the tax power and the Necessary and Proper Clause (which gives Congress the power to make laws "necessary and proper" for executing other powers granted to the federal government). This is likely to be most important Supreme Court Necessary and Proper Clause decision since at least NFIB v. Sebelius (2012), which ruled that a "proper" power permissible under the Clause is one that is "ancillary" to the implementation of an enumerated power; it cannot be a "great, substantive and independent" power. This case is likely to further clarify the meaning of "proper," perhaps by explicating in more detail what counts as a "great…and independent" power.
In the lower court decision in this case, the Fifth Circuit ruled that the law is not "proper" and even that it isn't "necessary." There is also a Sixth Circuit decision that went the other way, thereby creating a circuit split.
