You can hire a lawyer after being detained, but the role of a lawyer in detention is only to understand the charges, complaints, accusations, and applications for bail pending trial. Only after being arrested can you consult the file and fully intervene in the case. The Criminal Procedure Law stipulates that defense lawyers can provide legal aid to criminal suspects during investigation.
Legal objectivity:
Article 33 of the Criminal Procedure Law: In addition to exercising the right of defense, a criminal suspect or defendant may entrust one or two persons as defenders. The following persons may be entrusted as defenders: (1) lawyers; (2) A person recommended by a people's organization or the unit to which the criminal suspect or defendant belongs; (3) Guardians, relatives and friends of criminal suspects and defendants. A person who has been sentenced to punishment according to law or deprived of or restricted personal freedom shall not act as a defender. A person who has been dismissed from public office or has his lawyer's or notary's practice certificate revoked may not act as a defender, except the guardian or near relative of the criminal suspect or defendant.