NLRA § 12 — Penalties (29 U.S.C. § 162)
Makes it a misdemeanor to willfully resist, prevent, impede, or interfere with any member of the NLRB or any of its agents or agencies in the performance of duties under the Act.
Criminal penalties: fine not more than $5,000 or imprisonment not more than one year, or both.
Rarely invoked in practice — NLRB enforcement is almost entirely administrative (§ 10 procedures) rather than criminal.