What filings or on‑record statements would constitute a clear waiver of spousal privilege in a state criminal prosecution?

1. Testimony on the record: the clearest and most common waiver

When a spouse takes the witness stand and gives testimony adverse to the defendant, courts treat that act as an explicit waiver of testimonial privilege because the privilege belongs to the witness‑spouse and is defeated by their voluntary testimony (Trammel’s rule and subsequent commentary) ^{[1] [6]}. Multiple practitioner guides and defense resources state plainly that a spouse who elects to testify against a partner has waived the testimonial privilege, and judges routinely conduct a voir dire to ensure any waiver is knowing and voluntary ^{[2] [7]}.

2. Written waivers, affidavits, or plea agreements that include cooperation clauses

A signed affidavit or an explicit written waiver filed and entered on the court record—whether the spouse signs a waiver form, a witness statement admitted into evidence, or a cooperation clause in a plea deal obligating the spouse to testify—constitutes a clear on‑record waiver because it demonstrates intent to relinquish the privilege ^{[2] [6]}. Federal and state practitioners point to negotiated immunity or cooperation deals as customary routes by which prosecutors secure on‑record willingness to testify ^[6].

3. Pretrial depositions, grand jury testimony, and statements to prosecutors

Giving a recorded pretrial statement, testifying before a grand jury, or otherwise providing sworn or recorded statements to prosecutors that are later introduced or acknowledged on the record functions as a waiver of privilege in most jurisdictions, because the communication has been disclosed to third parties and the witness has chosen to become the prosecution’s source ^{[2] [3]}. Courts will still examine whether the disclosure was intended to be private and whether the spouse knowingly waived the privilege ^[3].

4. Formal on‑record acknowledgments or stipulations in court

A spouse’s explicit, on‑the‑record stipulation—made in open court or via written filing—that the privilege will not be asserted is a direct waiver; judges typically require such waivers to be knowing and voluntary and may query the witness outside the jury’s presence to verify understanding ^{[7] [1]}. Conversely, silence or failure to object when the spouse’s testimony is offered can be treated by some courts as forfeiture or waiver of the privilege ^[2].

5. Statutory and jurisdictional exceptions that make ‘waiver’ irrelevant

In many states the privilege never applies in certain prosecutions—such as crimes against the spouse, against their child, or some crimes of violence—so there is no waiver to execute; prosecutors can compel testimony regardless of any purported waiver (Nebraska statutory exceptions and similar state codes) ^{[4] [5]}. Because state law governs these contours, whether a filing or statement constitutes waiver depends on the jurisdiction’s allocation of the privilege and statutory exceptions ^{[8] [9]}.

6. Practical and procedural caveats, and where reporting leaves gaps

Case law and practitioner materials emphasize the witness‑spouse’s dominant control over waiver ^{[1] [2]}, but significant variability exists: some jurisdictions historically allowed defendant control or required mutual consent ^{[4] [5]}. Reporting compiled here documents common categories of waiver—testimony, written waivers, statements to prosecutors, plea cooperation—but does not catalog every state’s required words or form language; defense counsel preparation and judge colloquies are therefore critical to ensure an on‑record, knowing waiver where courts demand it ^{[7] [1]}.