The 2017 NFL Official Players Rules, page 23, article 8 states: “Throughout the period on game-day that a player is visible to the stadium and television audience (including pre-game warm-ups, in the bench area, or during post-game interviews in the locker room or during post-game interviews in the locker room or on the field) players are prohibited from wearing, displaying or otherwise conveying personal messages, either in writing or illustration, unless such message has been approved in advance by the League office.”
The NFL teams are owned by individuals or corporations who have the right to tell their employees (“overpaid” players) how they must conduct themselves while they are at their workplace (the football stadium).
Players must not politicize the sports arenas, but they can expound their personal views on their own time. Lastly, I would like to know how much of their $2.4 million average salaries they contribute to the causes they wish to support.
Salt Lake City