By this proceeding in mandamus petitioners seek to compel respondents to grant their application for the use of the auditorium of the Evening High School of Commerce at San Francisco on Friday evening, November 9, 1945.
Sections 19431-19433 of the Education Code (as partly amended in 1945) provide as follows:
“19431. There is a civic center at each and every public school building and grounds within the State where the citizens, parent-teachers’ association, Campfire Girls, Boy Scout troops, farmers’ organizations, clubs, and associations formed for recreational, educational, political, economic, artistic, or moral activities of the public school districts may engage in supervised recreational activities, and where they may meet and discuss, from time to time, as they may desire, any subjects and questions which in their judgment appertain to the educational, political, economic, artistic, and moral interests of the citizens of the communities in which they reside. Governing boards of the school districts may authorize the use, by such citizens and organizations of any other properties under their control, for supervised recreational activities.
“19432. Any use, by any individual, society, group, or organization which has as its object or as one of its objects, or is affiliated with any group, society, or organization which has as its object or one of its objects the overthrow or the advocacy of the overthrow of the present form of government of the United States or of the State by force, violence, or other unlawful means shall not be granted, permitted, or suffered.
“Any person who is affiliated with any organization, which advocates or has for its object or one of its objects the overthrow of the present government of the United States or any State, Territory, or Possession thereof, by force or violence or other unlawful means, or any organization of persons which advocates or has for its object or one of its objects the overthrow of the present government of the United States or any State, Territory, or Possession thereof, by force or violence or other unlawful means, is hereby declared to be and is characterized, a subversive element.
“Notwithstanding any of the other terms of this chapter, no such governing board shall grant the use of any school *200property to any person or organization who or which is a subversive element as herein defined.
“For the purpose of determination by such governing board whether or not such person or such organization of persons applying for the use of such school property, is a subversive element as herein defined, such governing board may require the making and delivery to such governing board, by such person or any members of such organization, of affidavits in form prescribed by such governing board, stating facts showing whether or not such person or organization is a subversive element as herein defined. . . .
“19433. The use of any public schoolhouse and grounds for any meeting is subject to such reasonable rules and regulations as the governing board of the district prescribes and shall in nowise interfere with the use and occupancy of the public schoolhouse and grounds, as is required for the purposes of the public schools of the State.”
Thus the statute, in making school buildings available as centers for community activities, establishes the condition that such activities must not disturb the educational program that constitutes the main and continuing purpose of the public schools. The respondent board may not only make reasonable regulations with regard to the use of the school auditorium for authorized purposes but may deny an application for its use if (1) such use would further, directly or indirectly, the overthrow of the present government of the United States or any State, Territory or Possession thereof, by force or violence or other unlawful means, or (2) would interfere with the use and occupancy of the public schoolhouse and grounds as required for the purposes of the public schools of the State. (See Goodman v. Board of Education, 48 Cal.App.2d 731 [120 P.2d 665].)
Petitioners have applied for the use of the auditorium for a mass meeting open to the public without charge, to acquaint the public with a proposed state constitutional amendment that petitioners intend to place on the ballot at the next general election to be known as “California Full Employment and Pension System.” They intend to present Gerald L. K. Smith as speaker. Petitioners’ application was filed on the prescribed form and bears the required signature of the school principal, certifying that the proposed use would not conflict with school programs or other scheduled meetings. The board has filed in this pro*201eeeding an affidavit of the principal “that the approval was limited to the availability of the auditorium for the evening applied for by said organization. That susbsequent to the approval of said request, affiant has been informed that Mr. Gerald L. K. Smith will be a speaker on the program scheduled for such use; that affiant has been informed that in each and every instance where Gerald L. K. Smith has spoken in a public building in the State of California, there have been extended picket lines at such building, resulting in a noisy and boisterous demonstration; that affiant is informed and believes, and on the basis of such information and belief alleges that if this application is granted, there will be extended picket lines comprising several thousand persons who will surround the building, causing noisy and boisterous demonstrations . . . that affiant is informed and believes, and on the basis of such information and belief, alleges that if this application is granted, numerous pupils enrolled at said school will refuse to go through the picket lines in order to attend classes; that the demonstrations, with attendant noises caused by such an extended picket line, will interfere with the use and occupancy of the said school and will interfere with the regular conduct of school work.” The board has also filed an affidavit of the Superintendent of Schools “that the demonstrations with attendant noises caused by such an extended picket line will interfere with the use and occupancy of the school building and will interfere with the regular conduct of the school work.” Representatives of various organizations, appeared before the board, and other organizations sent in written statements, protesting the use of the auditorium and announcing their intention to picket the meeting. The minutes of the board show “that the general reasons advanced for the opposition . . . was that Gerald L. K. Smith is an undesirable character, whose activities and speeches are attempting to divide the American people on the question of race and religion. That his activities are in no way different than those advocated by. leaders of the Fascist Government which has existed in Europe, and that because of this fact public property should not be used to assist his activities.” It was also urged by the opponents that the proposed meeting would interfere with school activities. The board members were advised by the board’s attorney that the application must be granted *202unless the proposed meeting would interfere with the regular school work.
Respondent board has emphasized in this proceeding that its refusal of petitioners’ application rests exclusively on the ground that in its opinion the proposed meeting would interfere with the school activities scheduled at that time. It is conceded that on the night of the proposed meeting there will be evening classes at the same school, although no classes are scheduled on Saturdays and Sundays. Moreover, it appears that there are auditoriums available in other schools where no classes are scheduled on the night of petitioners’ proposed meeting. The board has determined that, although the auditorium will not be required for the scheduled classes, the proposed meeting would greatly interfere with the conduct of the classes because the proposed speaker would arouse, as he has in Los Angeles and other cities, so much organized opposition that classes would be disturbed if not disrupted. The board had substantial evidence before it to support its determination that such an outcome was likely. Hence this court cannot declare that it was the board’s ministerial duty to grant petitioners’ application.
Petitioners do not deny that the board is justified in believing that the proposed meeting would be picketed, and that interference with the school work might ensue. They contend, however, that such interference would not be of their own doing and therefore cannot justify the board’s action in denying them the use of the auditorium on a school night. They invoke section 19501 of the Education Code, which provides: “Any person who wilfully disturbs any public school . . . meeting is guilty of a misdemeanor. . . .” They contend that it would be for the police to prevent any disturbance of the proposed meeting or of the school work, and that petitioners should not be penalized for any possible inability of the police department to prevent such disturbances.
Section 19501, however, is concerned only with wilful disturbance of public school meetings. It does not inhibit the expression of opposition to political meetings held in school auditoriums. It could not do so without infringing upon the constitutional right of free speech, which can be exercised by peaceful picketing. Speakers who express their opinions freely must run the risk of attracting opposition; *203they cannot expect their opponents to be silenced while they continue to speak freely. If a speaker in a school building or the opposition that he aroused attracted so much attention as to disturb school activities, it would not be for the police to curb those who incidentally caused the disturbance so long as their activities were lawful, but for the board to prevent the occurrence of such a disturbance. Neither a speaker nor his opponents are thereby stilled; they may express themselves fully and freely in school buildings as elsewhere whenever their activities do not bring in their wake a disturbance of the regular school program. (See Cox v. New Hampshire, 312 U.S. 569, 574 [61 S.Ct. 762, 85 L.Ed. 1049, 133 A.L.R. 1396].)
The board’s primary concern is with the maintenance of that program. It cannot dissipate its energies by seeking to guide and control or even to evaluate the strategy of opposing factions at every passing meeting that may be held in a school building. The activities of two opposed groups might operate in conjunction to interfere with school work. A speaker has a large part in fixing the character of his meeting; he cannot disclaim some share of the responsibility for whatever reactions his speech provokes. Again the disturbance might result, not from any activity of either the speaker or his opposition, but merely from an overflow audience. It is for the board to determine, not who would motivate a disturbance, but how serious is the risk of disturbance. The primary task of the schools is education. The statute establishes that the educational activities of schools shall at all times take precedence over other permissive but secondary uses of school buildings. In passing on an application for an extraneous use of a school auditorium the board must consider the probable effect of the proposed use on the regular school program and must deny one that would lead to an interference with that program. When the board denied petitioners’ use of the auditorium in a school on a night when regular classes were scheduled it acted well within the authority conferred Upon it by section 19433 of the Education Code providing that any meeting shall “in nowise interfere with the use and occupancy of the public sehoolhouse and grounds, as is required for the purposes of the public schools of the State.”
The alternative writ is discharged and th§ application for the peremptory writ of. mandato is denied,
*204Gibson, C. J., Shenk, J., Edmonds, J., Schauer, J., and Spence, J., concurred.