The National Football League, in a recent letter to the casino industry's largest trade group, stands by its position that the Las Vegas Super Bowl parties of years past won't fly this season. The letter, sent last month to the American Gaming Association, says Super Bowl parties that charge admission and events that show the game on a big screen or even on multiple television screens violate the NFL's broadcast copyright. The hard line on parties is a continuation of the league's uneasy relationship with gambling and Las Vegas, whose tourism bureau has been continually rebuffed in its efforts to broadcast advertising during the Super Bowl. The NFL fired off cease and desist letters to several Las Vegas casinos in January that had planned to host Super Bowl parties, leading to a last minute scramble that involved canceling or modifying the events in time for last season's faceoff between the New England Patriots and the Carolina Panthers. Read more from Las Vegas Sun.