Is the signature of criminal appeal valid?

Legal analysis: Criminal appeals generally require signatures to be effective. The signature of the appeal shall be signed by the parties concerned. However, if the defendant has authorized the lawyer to appeal and has the right to sign, the lawyer can sign the contract and submit the appeal according to the authorization.

Legal basis: Article 227 of the Criminal Procedure Law of People's Republic of China (PRC). Defendants, private prosecutors and their legal representatives who appeal have the right to appeal to the people's court at the next higher level in written or oral form if they refuse to accept the judgment or ruling of first instance of local people's courts at all levels. Defenders and close relatives of the defendant may appeal with the consent of the defendant. The parties to an incidental civil action and their legal representatives may appeal to the part of the incidental civil action in the judgment or ruling of first instance of the local people's courts at all levels. The defendant shall not be deprived of the right to appeal under any pretext.