Can a husband be his wife's defense lawyer?

Of course. According to the following provisions of the Criminal Procedure Law: Article 33 In the process of hearing a case, the people's court shall fully guarantee the defendant to exercise the right of defense as stipulated in Article 32 of the Criminal Procedure Law. However, the following persons shall not be entrusted as defenders:

(a) was sentenced to probation, the sentence has not been executed;

(2) A person who is deprived or restricted of personal freedom according to law;

(3) Persons without capacity or persons with limited capacity;

(4) Current employees of people's courts, people's procuratorates, public security organs, state security organs and prisons;

(5) People's jurors in our hospital;

(6) People who have an interest in the trial result of this case;

(7) Foreigners or stateless persons.

The people's court may allow the person specified in items (4), (5), (6) and (7) of the preceding paragraph to be a close relative or guardian of the defendant and be entrusted by the defendant to act as a defender.

Article 34 Where lawyers, people's organizations, citizens recommended by the defendant's unit, guardians and relatives of the defendant are entrusted as defenders, the people's court shall verify their identity certificates and power of attorney.