A California jury found 10 Muslim students guilty of misdemeanors for disrupting a 2010 campus speech by Israel's ambassador to the United States.The Volokh Conspiracy discusses the case:
In an incident that drew national attention, 11 Muslim students stood one by one and interrupted a February 2010 speech by Ambassador Michael Oren at the University of California, Irvine. Oren twice walked off the stage as students shouted "mass murderer!" and "war criminal!" before they were hauled out of the room by campus police. A planned Q&A session after the address was dropped.
The Orange County jury on Aug. 23 found 10 of the students guilty of two misdemeanor charges for conspiring to disrupt and then disrupting the speech. Charges against an eleventh student were dropped last month.
The 10 students were sentenced by Superior Court Judge Peter Wilson to 56 hours of community service and three years of probation, though the probation will be reduced to one year if the defendants complete their community service by Jan. 31 of next year.
According to The Orange County Register, Wilson said that jail time was not warranted because the students were "motivated by their beliefs and did not disrupt for the sake of disrupting."
The Muslim Student Union at UC Irvine, which organized the heckling, was suspended for a year by the school for violating its code of conduct, but four months later the suspension was changed to probation on appeal.
The relevant statute, Cal. Penal Code § 403, says: “Every person who, without authority of law, willfully disturbs or breaks up any assembly or meeting that is not unlawful in its character ... is guilty of a misdemeanor.” In re Kay (1970) held that, to be convicted under the statute, the prosecution must show “that the defendant  substantially impaired the conduct of the meeting by intentionally committing acts  in violation of implicit customs or usages or of explicit rules for governance of the meeting, of which he knew, or as a reasonable man should have known,” and  “the defendant’s activity itself — and not the content of the activity’s expression — substantially impairs the effective conduct of a meeting.”Legal nerds or nerd wannabes can read more there.