When a criminal suspect is in criminal detention, the public security organ will read him a detention certificate and ask him to sign it and press his fingerprint. If he refuses to hold back, the public security organ will write it down. However, there are also many people who are willing to sign and seal, but can't write. The case-handling personnel may sign on their behalf, but the words "Dai, this person has no writing ability" must be marked at the back. This will not affect the handler.