Doonesbury by Garry Trudeau for July 12, 1973
Transcript:
Justice: Good afternoon. Well, we've been conferring like crazy, and I think we have got ourselves another snappy 5-4 decision. The Supreme Court of the United States of America has reviewed the principle of executive privilege as it pertains to the First Lady. The consensus is that it does not apply. The Court thus directs Mrs. Nixon to make a Senate hearings appearance, inasmuch as it feels she shouldn't enjoy the immunity to which Presidential aides are currently entitled. Also, the Court rather thinks it would be a giggle.
Interestingly, spousal privilege also doesn’t apply. Congress is allowed to make their own rules for their hearing (other than pleading the 5th). So she can be forced to testify.