Government dues definition clarifies scope and officials authorised for attachment and recovery under customs attachment rules. Definitions identify operative terms for attachment and recovery: Act means the Customs Act, 1962; Government dues comprises duties, drawbacks, interest and penalties recoverable; Certificate is issued under section 142(1)(c); Principal Commissioner or Commissioner denotes the appointed senior official; Proper Officer is a subordinate not below Assistant Commissioner authorised to attach, sell defaulter property and realise amounts; Defaulter is any person from whom government dues are recoverable.