National Internal Revenue Code (NIRC)
Section 172. Detention of Package Containing Taxable Articles. - Any revenue officer may detain any package containing or supposed to contain articles subject to excise tax when he has good reason to believe that the lawful tax has not been paid or that the package has been or is being removed in violation of law, and every such package shall be held by such officer in a safe place until it shall be determined whether the property so detained is liable by law to be proceeded against for forfeiture; but such summary detention shall not continue in any case longer than seven (7) days without due process of law or intervention of the officer to whom such detention is to be reported.