Even in a well regulated society there are going to be gray areas in the law and judgement calls necessary, etc. If some jerk yells something one time at a meeting...no, I do not expect the police to descend immediately and take him away in the paddy wagon. However, if people are intentionally disrupting an otherwise organized meeting that they happen not to agree with...and after a reasonable attempt or two to quiet them down, they persist...then yes, I would call the police and report them as disorderly. Reasonable people will likely disagree as to where on that spectrum it really crosses over into disorderly conduct...hence the gray area I mention.
I will also say that we will all go blind and crazy together if we allow ourselves to have to legally define every nuance of every situation and human interaction that there could be, etc. Somewhere along the line, a polite, mature society has to be able to regulate themselves to respect others, even when there are disagreements.
My main point here is that there are first class jerks out there that only seek to disrupt the plans and speeches of others...and then throw up a lame excuse that they are protected by the 1st amendment, etc. (Understatement alert) I am very unlikely to support Hillary Clinton in 2016...but I would never go to one of her meetings and then seek to disrupt it...because I respect her right, and the rights of the others in the audience, however daft they may be
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, to describe her plans to them, etc.