Summary assessment protects revenue by permitting expedited assessment when delay would prejudice tax recovery and safeguards procedural review. Summary assessment permits expedited determination of tax liability by the proper officer, with prior permission of the Additional Commissioner or Joint Commissioner, where delay would prejudice revenue. If the taxable person is unascertainable and the liability arises from supply of goods, the person in charge of the goods is deemed to be the taxable person liable. The Additional Commissioner or Joint Commissioner may withdraw an erroneous summary order on review and direct that the matter proceed under the regular assessment procedure.