This is from the arrest warrant affidavit in the case of Kim Williams, the wife of Eric Williams, the former justice of the peace who is suspected of murdering three people in Kaufman County, Texas:
On April 16, 2013 an interview with defendant, Kim Lene Williams was conducted at the Kaufman County Law Enforcement Center. During the interview, Kim Williams confessed to her involvement to the scheme and course of conduct in the shooting deaths of Mark Hasse, Michael McLelland and Cynthia McLelland. Kim Williams described in detail her role along with that of her husband, Eric Williams whom she reported to have shot to death Mark Hasse on January 31, 2013 and Michael and Cynthia McLelland on March 30, 2013. During the interview, the defendant gave details of both offenses which had not been made public.
Kim has a privilege not to testify against Eric. She can waive it, though, and testify about what she saw and heard, including communications made to enable him to commit a crime.
But if her claim that he shot the three to death is based on his telling her about it after it was done, he has a privilege to keep her from testifying about that. She cannot waive that privilege.
He loaded his gun and drove toward the McLellands’ house she can testify to, but doesn’t have to.
He told me, “Honey, this is what I need you to do…” she can testify to, but doesn’t have to.
He told me, “Honey, this is what I did…” she can’t testify to if he says no.
I don’t think the “Furtherance of crime or fraud” exception to the spousal-communication privilege has been widely litigated, but I foresee it getting a thorough workout here.