Legal analysis: there is no clear legal provision on which finger to use when fingerprinting. In life practice, the right index finger is usually used to press the fingerprint. "By handprint" and "by handprint" are also called fingerprints, handprints and handprints, and they are also called handprints among the people. Civil acts (signing contracts, borrowing money, borrowing money, etc.) when fingerprinting. ) It is the index finger of the right hand. It is customary to use the thumb of the right hand in criminal cases (it is not easy to leak).

Legal basis: Article 490 of the Civil Code of People's Republic of China (PRC). If the parties enter into a contract in the form of a contract, the contract shall be established when the parties sign, seal or press their fingerprints. Before signing, sealing or fingerprinting, one party has fulfilled its main obligations, and the contract is established when the other party accepts it. A contract shall be concluded in written form as stipulated by laws, administrative regulations or agreed by the parties. If the parties do not do this in writing, but one party has fulfilled its main obligations and the other party accepts it, the contract is established.

Article 188 of the Criminal Procedure Law of the People's Procuratorate shall make an interrogation record when interrogating a criminal suspect. The interrogation record shall be faithful to the original words, legible, detailed and specific, and submitted to the criminal suspect for verification. If the criminal suspect has no reading ability, it shall be read to him. If there are any omissions or errors in the records, they should be supplemented or corrected. If a criminal suspect thinks that there is no mistake in the interrogation record, he shall sign or seal it page by page and press his handprint. On the last page, he should write "I have read the above record (read it to me), and it is consistent with what I said", and at the same time sign or seal it, fingerprint it and date it. If the criminal suspect refuses to sign, seal or fingerprint, it shall be noted in the record. The procurator and the clerk of the interrogation shall also sign the record.