dissenting.
The part of the oath that says “I will oppose the overthrow of the government of the United States of America or of this Commonwealth by force, violence or by any illegal or unconstitutional method” is plainly unconstitutional by our decisions. See Board of Education v. Barnette, 319 U. S. 624, 634.
*688Advocacy of basic fundamental changes in government, which might popularly be described as “overthrow,” is within the protection of the First Amendment even when it is restrictively construed. In Brandenburg v. Ohio, 395 U. S. 444, a case involving criminal syndicalism, this Court ruled that a State may not “forbid or proscribe advocacy of the use of force or of law violation except where such advocacy is directed to inciting or producing imminent lawless action and is likely to incite or produce such action.” Id., at 447. The same idea was put in somewhat different words in Noto v. United States, 367 U. S. 290, 297-298, that “abstract teaching” of overthrow is protected activity as contrasted to “preparing a group for violent action and steeling it to such action.” And see Yates v. United States, 354 U. S. 298, 318.
The present oath makes such advocacy a possible offense under a restrictive reading of the First Amendment.
The views expressed by Mr. Justice Black and me give the First Amendment a more expansive reading. We have condemned loyalty oaths as “manifestation [s] of a national network of laws aimed at coercing and controlling the minds of men. Test oaths are notorious tools of tyranny. When used to shackle the mind they are, or at least they should be, unspeakably odious to a free people.” Wieman v. Updegraff, 344 U. S. 183, 193 (Black, J., concurring). And see Speiser v. Randall, 357 U. S. 513, 532 (Douglas, J., concurring). We said in Brandenburg that the protection of the First Amendment as applied to the States through the Fourteenth does not depend on the “quality of advocacy,” since that “turns on the depth of the conviction.” 395 U. S., at 457 (Douglas, J., concurring). The line between the permissible control by a State and the impermissible control is “the line between ideas and overt acts.” Id., at 456. “The First Amendment . . . leaves the way wide open for people to favor, discuss, advocate, or incite causes *689and doctrines however obnoxious and antagonistic such views may be to the rest of us.” Yates v. United States, supra, at 344 (Black, J., concurring and dissenting). This oath, however, requires that appellee “oppose” that which she has an indisputable right to advocate.1 Yet the majority concludes that the promise of “opposition”— exacted as a condition of public employment2 — is a mere redundancy which does not impair appellee’s freedom of expression.3
*690It is suggested, however, that because only the second portion of the oath is unconstitutional we should sever the two clauses and uphold the first. Even on this assumption, the entire oath must fall. This Court should, of course, base its decisions upon local law where, in so doing, we may avoid deciding federal constitutional questions. Here, we have been cited to no evidence of a legislative intent to separate the two clauses of the oath. This case is thus governed by Pedlosky v. Massachusetts Institute of Technology, 352 Mass. 127, 224 N. E. 2d 414 (1967), where the Supreme Judicial Court of Massachusetts was confronted with a two-part test oath similar in effect to the one before us.4 “The substance of the oath [was] not confined merely to a declaration of support of the Federal and State Constitutions. It equally concern [ed] an undertaking by the plaintiff that T will faithfully discharge the duties of the position of assistant professor of mathematics according to the best of my ability.' ” Id., at 128-129, 224 N. E. 2d, at 416. Finding the oath to be “altogether too vague a standard to enforce judicially” and being without evidence “whether the Legislature would have enacted [it] without the [invalid] provision,” the court was unable to hold that the provisions were severable, and thus unanimously struck down the entire oath. Id., at 129, 224 N. E. 2d, at 416.
I would follow the lead of the Supreme Judicial Court of Massachusetts — the court which has the final word on how the statutes of that State are to be construed — and hold that the entire oath must fall.
*691I conclude that whether the First Amendment is read restrictively or literally as Jefferson would have read it, the oath which the District Court struck down, 300 F. Supp. 1321, is plainly unconstitutional. I would affirm its judgment.
The majority makes the suggestion that “we might be faced with a different question” if there were “a record of actual prosecutions or harassment through threatened prosecutions.” Ante, at 685. Here, appellee has been discharged from employment and denied her source of livelihood because of her refusal to subscribe to an unconstitutional oath. If the oath suffers from constitutional infirmities, then it matters not whether the penalties imposed for refusing to subscribe to it were criminal or the denial of employment.
The Court is correct when it says “there is no constitutionally protected right to overthrow a government by force, violence, or illegal or unconstitutional means,” ante, at 686, but that has no bearing on the present case. What is involved here is appellee’s right to espouse and advocate ideas which may be unpopular to some. How we can honor that right to advocate while exacting the promise to “oppose,” the Court leaves unanswered.
The majority first chides the District Court for taking “a literal approach” and “giv[ing] [the word 'oppose’] a dictionary meaning.” The majority then reads “oppose” to be a mere “negative implication of th[e] notion” of “a commitment to abide by our constitutional system” not requiring “specific, positive action.” Ante, at 683, 684. Having thus emasculated the word, the majority then labels it as “redundant” and a “repetition,” ibid., and concludes that the oath, in its entirety, is simply “to abide by the constitutional system in the future.” Ante, at 686.
If the oath is void for vagueness or overbreadth, it is because the common meaning of its words is so imprecise or so farreaching as to place a “chilling effect” upon constitutionally protected expression. This vice — readily apparent in the present oath — is emphasized rather than avoided by the majority’s opinion. The tortured route which the majority takes to give this oath a supposedly constitutional interpretation merely emphasizes the unconstitutional effect those words would have were they to be given their natural meaning.
The oath provided: “I do solemnly swear (or affirm) that I will support the Constitution of the United States and the Constitution of the Commonwealth of Massachusetts, and that I will faithfully discharge the duties of the position of (insert name of position) according to the best of my ability.”