When people are charged with crimes, their spouses have certain privileges that protect the marriage from state intrusion. It is necessary to recognize that the marriage must be valid in order for these privileges to apply.
Either spouse has the ability to refuse disclosure of any communications with the other spouse. This husband-wife privilege only extends to testimony and not to statements that were made to law enforcement agents. If the couple is divorced later on, the privileges only extend to the communications that the two individuals had while they were married. Additionally, certain communications involving business or abusive language aimed at one of the spouses are not protected.
Spouses also have immunity from having to testify against the other spouse. This means that the prosecution cannot call the spouse to the witness stand. In federal courts, the spouse is allowed to testify if they so choose; however, they cannot be compelled to testify. In some states, the accused person may stop their spouse from testifying against them. In California, the accused person cannot stop their spouse from testifying. Again, this immunity only protects the spouses as long as they remain married.
If a person is accused of being involved in a crime, the accused person's attorney may use the evidence available to create a strong criminal defense to potentially protect the person against the consequences. An attorney might be able to work with the accused person's spouse to invoke their marital testimonial privilege and their marital communication privilege to help the case. If the evidence against the person is not clear or is circumstantial at best, the defense team may raise doubt that the person was involved in the crime. Otherwise, the attorney may work to reduce the potential consequences by negotiating a plea deal.