FREE SPEECH — It's claimed in some quarters that the students who recently orchestrated a serial shout-down of a speech at U.C. Irvine by the Israeli ambassador to the U.S. were exercising their First Amendment right to protest.  The California Supreme Court has held that there can be in effect a constitutional right to heckle, but not where it intentionally brings a meeting to a standstill and violates standing rules or customs, known by the audience, for gatherings of the type in question. 

In In re Kay,
1 Cal. 3d 930 (1970), the court concluded that hecklers at a Congressman's speech given at an evening Fourth of July, 1968 celebration and picnic in a public park in Coachella should not have been prosecuted for violation of the nearly century-old Penal Code Section 403, which provided, "Every person who, without authority of law, willfully disturbs or breaks up any assembly or meeting, not unlawful in its character, . . . is guilty of a misdemeanor."

The court held that this statute was constitutional only if interpreted to mean that

participants at a meeting may express disagreement but must not violate explicit rules or implicit customs and usages, pertaining to the meeting,
of which they knew or should have known; such activity, when it is
intentional and when it substantially impairs the conduct of a
meeting, violates section 403.

Anyone watching a video of the Irvine speech would have to conclude that the disruption was deliberate, coordinated, actually effective in thwarting the speech as planned, and in a context where the rules of courtesy for guest speakers were repeatedly emphasized by the ambassador's faculty hosts.  In re Kay is not likely to help these students and will probably strip them of any First Amendment defense.