The Constitution does not guarantee public employment. City, State and Nation are not confined to making provisions appropriate for securing competent professional discharge of the functions pertaining to diverse *725governmental jobs. They may also assure themselves of fidelity to the very presuppositions of our scheme of government on the part of those who seek to serve it. No unit of government can be denied the right to keep out of its employ those who seek to overthrow the government by force or violence, or are knowingly members of an organization engaged in such endeavor. See Gerende v. Board of Supervisors of Elections, 341 U. S. 56.
But it does not at all follow that because the Constitution does not guarantee a right to public employment, a city or a State may resort to any scheme for keeping people out of such employment. Law cannot reach every discrimination in practice. But doubtless unreasonable discriminations, if avowed in formal law, would not survive constitutional challenge. Surely, a government could not exclude from public employment members of a minority group merely because they are odious to the majority, nor restrict such employment, say, to native-born citizens. To describe public employment as a privilege does not meet the problem.
This line of reasoning gives the direction, I believe, for dealing with the issues before us. A municipality like Los Angeles ought to be allowed adequate scope in seeking to elicit information about its employees and from them. It would give to the Due Process Clause an unwarranted power of intrusion into local affairs to hold that a city may not require its employees to disclose whether they have been members of the Communist Party or the Communist Political Association. In the context of our time, such membership is sufficiently relevant to effective and dependable government, and to the confidence of the electorate in its government. I think the precise Madison would have been surprised even to hear it suggested that the requirement of this affidavit was an “Attainder” under Art. I, § 10, of the Constitution. For reasons outlined in the concurring opinion in United *726States v. Lovett, 328 U. S. 303, 318, I cannot so regard it. This kind of inquiry into political affiliation may in the long run do more harm than good. But the two employees who were dismissed solely because they refused to file an affidavit stating whether or when they had been members of the Communist Party or the Communist Political Association cannot successfully appeal to the Constitution of the United States.
A very different issue is presented by the fifteen employees who were discharged because they refused to take this oath:
“I . . . do solemnly swear (or affirm) . . . that I . . . have not, within said period [from December 6, 1943], been or become a member of or affiliated with any group, society, association, organization or party which advises, advocates or teaches, or has, within said period, advised, advocated or taught, the overthrow by force, violence or other unlawful means of the Government of the United States of America, or of the State of California.”
The validity of an oath must be judged on the assumption that it will be taken conscientiously. This ordinance does not ask the employee to swear that he “knowingly” or “to the best of his knowledge” had no proscribed affiliation. Certainty is implied in the disavowal exacted. The oath thus excludes from city employment all persons who are not certain that every organization to which they belonged or with which they were affiliated (with all the uncertainties of the meaning of “affiliated”) at any time since 1943 has not since that date advocated the overthrow by “unlawful means” of the Government of the United States or of the State of California.
The vice in this oath is that it is not limited to affiliation with organizations known at the time to have advocated overthrow of government. We have here a very different *727situation from that recently before us in Gerende v. Board of Supervisors, 341 U. S. 56. There the Attorney General of Maryland assured this Court that he would advise the appropriate authorities to accept as the oath required by State law from a candidate for office, an affirmation that he is not engaged in the attempt to overthrow the Government by force or violence and that he is not knowingly a member of an organization engaged in such an attempt. The Attorney General did not give this assurance as a matter of personal relaxation of a legal requirement. He was able to give it on the basis of the interpretation that the Court of Appeals of Maryland, the highest court of that State, had placed upon the legislation. No such assurance was remotely suggested on behalf of Los An-geles. Naturally not. Nothing in the decisions under review would warrant such restricted interpretation of the assailed ordinance.* To find scienter implied in a criminal statute is the obvious way of reading such a statute, for guilty knowledge is the normal ingredient of criminal responsibility. The ordinance before us exacts an oath as a condition of employment; it does not define a crime. It is certainly not open to this Court to rewrite the oath required by Los Angeles of its employees, after the oath as written has been sustained by the California courts.
If this ordinance is sustained, sanction is given to like oaths for every governmental unit in the United States. Not only does the oath make an irrational demand. It is *728bound to operate as a real deterrent to people contemplating even innocent associations. How can anyone be sure that an organization with which he affiliates will not at some time in the future be found by a State or National official to advocate overthrow of government by “unlawful means”? All but the hardiest may well hesitate to join organizations if they know that by such a proscription they will be permanently disqualified from public employment. These are considerations that cut deep into the traditions of our people. Gregariousness and friendliness are among the most characteristic of American attitudes. Throughout our history they have been manifested in “joining.” See Arthur M. Schlesinger, Sr., Biography of a Nation of Joiners, published in 50 American Historical Review 1, reprinted in Schlesinger, Paths to the Present, 23.
Giving full scope to the selective processes open to our municipalities and States in securing competent and reliable functionaries free from allegiance to any alien political authority, I do not think that it is consonant with the Due Process Clause for men to be asked, on pain of giving up public employment, to swear to something they cannot be expected to know. Such a demand is at war with individual integrity; it can no more be justified than the inquiry into belief which Mr. Justice Black, Mr. Justice Jackson and I deemed invalid in American Communications Assn. v. Douds, 339 U. S. 382.
The needs of security do not require such curbs on what may well be innocuous feelings and associations. Such curbs are indeed self-defeating. They are not merely unjustifiable restraints on individuals. They are not merely productive of an atmosphere of repression uncongenial to the spiritual vitality of a democratic society. The inhibitions which they engender are hostile to the best conditions for securing a high-minded and high-spirited public service.
*729It is not for us to write the oath that Los Angeles may-exact. And so as to the fifteen employees I think the case should go back to the State court, with instructions that these petitioners be reinstated unless they refuse to take an oath or affirmation within the scope indicated in this opinion.
Nothing in the decision or opinion of the Supreme Court of California in People v. Steelik, 187 Cal. 361, 203 P. 78, indicates that the courts of California would at their own instance read into the Los Angeles oath a limitation which is not there expressed. In the Steelik case the court was considering a statute which provided that “Any person who . . . [organizes or assists in organizing, or is or knowingly becomes a member of, any organization” teaching criminal syndicalism is guilty of a felony. Cal. Stat. 1919, c. 188, § 2. The court held only that the word “knowingly” qualified the word “is” in addition to the word “becomes.”