Is it necessary to hire two lawyers for criminal appeal?

In criminal cases, the duty of a lawyer as a defender is to provide materials and opinions on whether a criminal suspect or defendant is innocent, light or relieved of criminal responsibility according to facts and laws, and to safeguard the litigation rights and other legitimate rights and interests of the criminal suspect or defendant. A criminal suspect has the right to entrust a defender from the day when he is interrogated for the first time by the investigation organ or compulsory measures are taken, but whether to entrust him or not shall be decided according to the wishes of the criminal suspect.