Incentive for Aggression in American Football

Abstract

This chapter focuses on the United States’ National Football League (NFL) and the continuing attempt to control the level of violence inherent in the game. The study uses data from 1995 to 2009 to analyze the effect of violence and aggression on the success of a team and on fan attendance. Results show that penalties are negatively associated with wins from 1995 through 2005; after 2005, this relationship is statistically insignificant, although trends apparent in the data make it essential to watch the progression of this relationship. In addition, data suggest a correlation between attendance and more egregious rule infractions over the past five seasons; however, such correlation is not found to be statistically significant.

Appendix

History of NFL rules since 1955
1955	The ball is dead immediately if the ball carrier touched the ground with any part of his body except his hands or feet while in the grasp of an opponent
1956	Grabbing an opponent’s facemask (other than the ball carrier) is illegal
1962	Grabbing any player’s facemask is illegal
1974	Roll-blocking and cutting of wide receivers was eliminated; the extent of downfield contact a defender could have with an eligible receiver was restricted; the penalties for offensive holding, illegal use of the hands, and tripping were reduced from 15 to 10 yards; wide receivers blocking back toward the ball within 3 yards of the line of scrimmage were prevented from blocking below the waist
1977	Defenders permitted to make contact with eligible receivers only once; the head slap was outlawed; offensive linemen were prohibited from thrusting their hands to an opponent’s neck, face, or head; and wide receivers were prohibited from clipping, even in the legal clipping zone
1978	Rules changes permitted a defender to maintain contact with a receiver within 5 yards of the line of scrimmage, but restricted contact beyond that point
1979	Changes prohibited players on the receiving team from blocking below the waist during kickoffs, punts, and field-goal attempts; prohibited the wearing of torn or altered equipment and exposed pads that could be hazardous; extended the zone in which there could be no crack back blocks; and instructed officials to quickly whistle a play dead when a quarterback was clearly in the grasp of a tackler
1980	Under the heading of “personal foul,” players were prohibited from directly striking, swinging, or clubbing on the head, neck, or face. A penalty could be called for such contact whether or not the initial contact was made below the neck area
1996	Hits with the helmet or to the head by the defender will be flagged as personal fouls and subject to fines
1997	No player may remove his helmet while on the playing field (except during timeouts and between quarters)
1999	Clipping illegal around the line of scrimmage just as it is on the rest of the field
2001	Prohibition of anabolic steroids and related substances was strengthened to include supplements containing ephedrine and other high-risk supplements
2002	The chop-block technique is illegal on kicking plays. It is illegal to hit a quarterback helmet-to-helmet anytime after a change of possession
2005	Adoption of the Olympic testosterone testing standard, tripling the number of times a player can be randomly tested during the off-season from two to six, adding substances to the list of banned substances, and putting new language in the policy to allow for testing of designer drugs and other substances that may have evaded detection
	Players prohibited from grabbing the inside collar of the back or side of the shoulder pads and immediately pulling down the runner
	The “peel back” block is illegal. Previously, a player aligned in the tackle box could hit an opponent on the side and below the waist from any direction
	No unnecessary roughness, including unnecessarily running, diving into, cutting, or throwing the body against or on a player who is out of the play before or after the ball is dead
	A kicker or punter standing still after the ball has been kicked is out of the play and must not be unnecessarily contacted by the receiving team until he assumes a distinctly defensive position. An opponent may not unnecessarily initiate helmet-to-helmet contact to the kicker/punter at anytime during the kick or during the return
2006	Rushing defenders must make a conscious effort to avoid low hits on the quarterback
	Prohibits blocking in the back above the waist applies to a player of the kicking team while the ball is in flight during a scrimmage kick
	Increased the scope of the “horse-collar” tackle rule
	During a field-goal attempt or a PAT, any defensive player within 1 yard of the line of scrimmage at the snap must have his helmet outside the snapper’s shoulder pad
	No more than six players can line up on the same side of a formation on a kickoff
2007	Players will be subject to a fine from the league for playing with an unbuckled chin strap
	15-Yard penalty (rather than 5 yards) for a player blocking below the waist against an eligible receiver while the quarterback is in the pocket
2008	No incidental face mask rule; 15-yard penalty for any other face mask call remains
2009	New and expanded guidelines on return-to-play for any player who sustains a concussion. Protection for defenseless players standardized and expanded, protection of a player who has just completed a catch from blows to the head or neck by an opponent who launches. Additional protection also given to long snappers. Play will now stop if a ball carrier’s helmet is removed
	Initial contact to the head of a defenseless receiver will draw a 15-yard penalty
	The initial force of a blindside block cannot be delivered by a helmet, forearm, or shoulder to an opponent’s head or neck
	On kickoffs, no blocking wedge of more than two players will be allowed
	On onside kicks, the kicking team cannot have more than five players bunched together in pursuit
	A defensive player on the ground may no longer lunge or dive at the quarterback’s lower legs
2010	A play will now be whistled dead if a ball carrier loses his helmet while still in possession of the football
	During field goals and punts, opposing defensive players cannot line up directly over the center. They must have their entire body outside the snapper’s shoulder pads
	Officials will call more penalties for spearing or launching at a defenseless player. Defenseless players are players who: just threw a pass, attempt to catch a pass, are in the grasp, attempting a kick, on the ground at the end of the play. Also, the centers (snappers) for field goal and extra points are considered defenseless

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