The D.A. tells the judge that Mr. Dodson is waiving his spousal privilege and is prepared to testify against Mrs. Dodson. While he can waive his own testimonial immunity, Mrs. Dodson has her own communication immunity which she can invoke to prevent him from testifying about anything they said in confidence.
The scene was 1932, Elias Birchard 'E.B.' Jonathan told his client Emily Dodson he could get her a deal of 20 years at the California Women's Prison in Chino. Chino's Women Prison did not open until 1952, replacing Tehachapi Women Prison which opened in 1932.