the New England Patriots were disciplined by the league for videotaping New York Jets' defensive coaches' signals during a September 9, 2007 game. Videotaping opposing coaches is not illegal in the NFL but there are designated areas allowed by the league to do such taping. The Patriots were videotaping the Jets' coaches from their own sideline which is not allowed. The act was deemed by NFL Commissioner Roger Goodell to be in violation of league rules, causing him to say when penalizing the Patriots that this episode represents a calculated and deliberate attempt to avoid long-standing rules designed to encourage fair play and promote honest competition on the playing field.
Depending on where you are when you do it.
I will assume they were video taping the defensive coaches in an effort to steal their signals or add their picture to Ashley Madison profiles...The Patriots were videotaping the Jets' coaches from their own sideline which is not allowed.
If they were standing in the stands they were within their rights to videotape the defensive coaches for the purpose of Ashley Madison profiles (stealing defensive signs/signals) - If they are standing on their sidelines it is illegal. Please correct if I am wrong.