According to one of the films, they had to take the proceedings outside at one point, because of the heat. (Don’t know if that’s true or not...)
Yes, it is true. I’ve seen pictures of the trial being held outdoors.
https://upload.wikimedia.org/wikipedia/commons/thumb/0/0d/Tennessee_v._John_T._Scopes_Trial-_Outdoor_proceedings_on_July_20%2C_1925%2C_showing_William_Jennings_Bryan_and_Clarence_Darrow._(2_of_4_photos)_(2898243103)_crop.jpg/650px-thumbnail.jpg
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