Carrier liability under customs law: failure to account goods can trigger confiscation, penalties and possible waiver if explained. Carrier obligations under the Customs Act expose the person in charge to confiscation where conveyances are used to conceal, destroy, unlawfully unload, disobey stop orders, arrive with substantial cargo missing, or are used for smuggling unless lack of owner knowledge is shown. Under separate provisions, failure to account for imported or transshipped goods not unloaded at destination, or shortages at specific destinations, attracts penalties-potentially twice the duty on unaccounted goods-subject to possible waiver if satisfactorily explained to the competent officer.