Parades:Recreation or Speech?

An Irish gay and lesbian group wanted to march in Boston's annual Saint Patrick's Day parade.The organizers of the parade wanted to stop them.The gay and lesbian group said a parade is a public recreational event，and therefore，civil rights law protected them against discrimination in public accommodations.The parade organizers claimed a parade is an expression of beliefs，really an act of speech.Their right to say what they wanted—by excluding from the parade those with a different message—should be protected by the First Amendment.Is a parade a public recreational event or an act of self-expression?Might it be both?What would you do if you were a justice on the Supreme Court and had to decide one way or the other?(https://www.daowen.com)