I thought that Tucker Carlson was being lexically creative when he walked back his statement that Michael Vick should have been executed for his dogfighting sins:
"This is what happens when you get too emotional," Carlson said [...] "I'm a dog lover…I love them and I know a lot about what Michael Vick did … I overspoke. I'm uncomfortable with the death penalty in any circumstance. Of course I don't think he should be executed, but I do think that what he did is truly appalling."
But no: overspeak is a well-attested word, which the OED glosses as "trans. To overstate or exaggerate; to make exaggerated claims for" or "intr. To speak too strongly, to exaggerate; to speak too much. Also trans. (refl.)". There are relevant citations back to the 17th century:
a1661 T. Fuller Worthies (1662) Hants. 5 Seing ill usage‥may make a Sober man Overspeak in his passion.
The OED's entry for overspeak also includes this intriguing and somewhat shocking quote:
1935 S. Ervin & W. M. Bennett Henry Ford vs. Truman H. Newberry xvii. 551 Of course, as the ‘niggers’ say, he may have ‘overspoke himself’, but still he is not a ‘nigger’.
The cited work is Spencer Ervin, Henry Ford vs. Truman H. Newberry: The Famous Senate Election Contest. (A Study in American Politics, Legislation and Justice), 1935. A full-text version of this book, as digitized by Google, is available from the Hathi Trust. From its introduction:
At the general election of 1918 Truman H. Newberry was elected United States Senator from Michigan, having previously won the Republican nomination in a vigorous primary context against Henry Ford. In this primary context between two wealthy candidates a large amount of money was spent; sums very far in excess of the maximum limit prescribed by the Corrupt Practices Act. Accordingly, Senator Newberry was haled before a Federal court and convicted of having been a party to the violation of this law. The conviction, however, was appealed to the Supreme Court, which ruled, in a five-to-four decision, that Congress had exceeded its powers in attempting to regulate primary elections. [...]
The conviction of Senator Newberry was therefore reversed and, although the Senate was urged to unseat him, under the provision which emposers it to judge the qualifications of its own members, it declined by a close vote to do so. It did, however, pass a vote of censure which declared the expenditures in the primary contest to have been exessive and contrary to sound public policy. Subsequently Senator Newberry resigned [...]
During the proceedings in the Senate, Newberry was accused of perjury with respect to the Senate forms that he filled out about his expenditures. Ervin quotes "one passage, eminent for its bitterness even in that bitter debate", contributed by John Sharp Williams, then a Democratic senator from Mississippi. The whole thing is worth reading. Embedded in a bit more context, the OED's quotation runs like this:
He goes on:
"The campaign for my nomination as United States Senator has been voluntarily conducted by friends in Michigan—"
I reckon by that that he did not even have to announce himself as a candidate—
"I have taken no part in it whatever—"
Now, Senators, I wish you would watch that. Of course, as the "niggers" say, he may have "overspoke himself," but still he is not a "nigger." He was a lieutenant commander in the Navy. He was Assistant Secretary of the Navy at one time. He is now seeking to be a Senator of the United State. This is written in his own handwriting—
"I have taken no part in it whatever—"
Do you believe that? If there are six Senators on this floor who believe that, they are not fit to be Senators, because they are too gullible for anything.
The rhetoric here is not completely clear to me — why are six Senators more gullible than one? — but the racial slur seems to be that as a white man, Newberry should be held to a higher standard of truthfulness.
And then there's the background assumption that use of "overspoke" is a feature of African-American Vernacular English. I couldn't find any independent evidence for this. In fact, a quick historical usage survey suggests a rather different hypothesis.
The phrase "overspoke himself" occurs seven times in the Proquest Historical Newspapers index. None of these passages are have any discernable connection with AAVE. Three of them are due to Westbrook Pegler, who has never before been identified as a columnist of color. Two of his uses refer to taboo language in sports, one on the part of the announcer of a Harvard-Dartmouth football game and the other due to the baseball player Heinie Manush. Pegler's third use, from December 25, 1940, refers to what he saw as a mis-step by Harold Ickes in arguing for a plan to allow Jewish refugees into the Virgin Islands:
At this Christmas time I should like to say that in the matter of loving one's enemies, I am shooting a perfect score, and will greet the day with a serene conscience. [...]
I thought for a time there, just after election, that I might have to ask waivers on old Harold L. (for Lovable) Ickes, but the talk of unity proved to be just talk, after all, and he is now back in action in a most satisfactory way, trying to import whole batches of refugees, regardless of the possibility that most or all of them would be Communists, and drop them into a lovely vacation land in the Virgin Islands, whence they could filter into the United States.
As Mr. Ickes so often does, he overspoke himself, however, and it seem likely that the citizens will fix his wagon if he tries any funny business in this respect, "without passports or diplomatic formalities."
A story by Irving Vaughn in the Chicago Tribune of 6/22/1941 again refers to off-color language in a sports context:
Ben Chapman, who was installed in left field in Myril Hoag's place, also belted a homer, later leaving the scene at the request of Umpire Ernie Stewart. Ben overspoke himself on a called third strike in the fifth.
The Senate Armed Services Committee decided today not to summon Gen. George S. Brown, the Chairman of the Joint Chiefs of Staff, for an explanation of his critical comments about Jews in the United States. [...]
Senator Stennis told reporters that General Brown had "made a mistake," "overspoke himself" and "got out of bounds."
Senator John C. Stennis, Democrat of Mississippi, seems even less likely than Mr. Pegler to have had any recent African ancestors.
The seventh hit is another quotation from a southern senator, this time Jesse Helms, Republican of North Carolina (Robin Toner, "Senate, Ending Impasse, Approves Envoy to China", 11/6/1985):
Mr. Helms had blocked Mr. Spain's nomination until the nomiee explained questions he had raised in an article critical of the ambassadorial appointment process.
Mr. Helms told the Senate tonight, "Mr. Spain recognizes now that he overspoke himself when he wrote the article."
So to sum it all up, it seems to me that John Sharp Williams himself "overspoke himself", back in 1919. What he should have said was
Now, Senators, I wish you would watch that. Of course, as the white southern senators, sportswriters, and right-wing pundits say, he may have "overspoke himself," but still he is not a white southern senator, a sportswriter, or a right-wing pundit. He was a lieutenant commander in the Navy. He was Assistant Secretary of the Navy at one time. He is now seeking to be a Senator of the United State. This is written in his own handwriting—
And this usage note would also fit Tucker Carlson better than Williams' original version does.