Legal analysis: 1. For national, provincial and municipal key tax source enterprises, a combination of directional and non-directional spot checks is adopted, with a spot check ratio of about 21% every year. In principle, the inspection is conducted once every five years. For non-key tax source enterprises, directional spot checks are mainly adopted, supplemented by non-directional spot checks, and the annual spot check ratio does not exceed 3%. For non-enterprise taxpayers, non-directional spot checks are mainly adopted, and the annual spot check ratio does not exceed 1%. For enterprises listed in the list of abnormal objects of tax inspection, it is necessary to intensify spot checks and increase the proportion and frequency of spot checks. Tax inspection objects that have been randomly selected within 3 years are not included in the scope of random sampling. 2. Invoices charged by enterprises for meeting fees, meals, office supplies, commissions and various handling fees shall be listed as mandatory invoices for key inspection. Such invoices should be checked and compared one by one, focusing on whether enterprises use false invoices and other illegal documents to fabricate business projects and falsely list costs and expenses.

legal basis: "tax inspection procedures" article 4 the inspection bureau shall carry out tax inspection under the leadership of its tax bureau. The superior inspection bureau manages, guides, evaluates and supervises the inspection business of the subordinate inspection bureau, and directs and coordinates the law enforcement and case handling. Inspection bureaus of state taxation bureaus and local taxation bureaus at all levels shall strengthen contact and cooperation, exchange information and share information in a timely manner, conduct joint inspections on the same inspected object as far as possible, and make treatment decisions respectively; Article 5 When investigating and handling tax violation cases, the Inspection Bureau shall implement the principle of selecting cases, inspecting, hearing and implementing the division of labor. The Inspection Bureau shall set up departments of case selection, inspection, trial and execution to implement case selection, inspection, trial and execution respectively; Article 6 Tax inspectors shall keep confidential the business secrets and personal privacy of taxpayers and withholding agents according to law. The illegal tax acts of taxpayers and withholding agents do not belong to the scope of confidentiality.