These are the penalties that make football coaches yell at their players because they cost the team 15 yards — the stiffest penalties (other than ejection or pass interference) in American football:
A tackler using his helmet to butt, spear, or ram an opponent: When a player uses the top and forehead of the helmet, plus the face mask, to unnecessarily butt, spear, or ram an opponent. The officials monitor particular situations, such as when a
Passer is in the act of throwing or has just released a pass
Receiver is catching or attempting to catch a pass
Runner is already in the grasp of a tackler
Kick returner or punt returner is attempting to field a kick in the air
Player is on the ground at the end of a play
A punter, placekicker, or holder simulates being roughed by a defensive player: When these players pretend to be hurt or injured or act like a defensive player caused them actual harm when the contact is considered incidental.
Chop block: When an offensive player blocks a defensive player at the thigh or lower while another offensive player occupies that same defensive player by attempting to block him or even simulating a blocking attempt.
Clipping below the waist: When a player throws his body across the back of the leg(s) of an opponent or charges, falls, or rolls into the back of an opponent below the waist after approaching him from behind, provided that the opponent isn't a ball carrier or positioned close to the line of scrimmage. However, within 3 yards on either side of the line of scrimmage and within an area extended laterally to the original position of the offensive tackle, offensive linemen can block defensive linemen from behind.
Delay of game at the start of either half: When the captains for either team fail to show up (or fail to show up in uniform) in the center of the field for the coin toss three minutes prior to the start of the game. A team whose captains fail to show loses the coin toss option and is penalized from the spot of the kickoff. The other team automatically gets the coin-toss choice.
Face mask: When a tackler twists, turns, or pulls an opponent by the face mask. Because this move is particularly dangerous, the penalty is 15-yards and an automatic first down. If the referee considers his action flagrant, the player may be ejected from the game.
Fair catch interference: When a player from the kicking team prevents the punt or kick returner from making a path to the ball or touching the ball prior to the ball hitting the ground. This penalty isn't called when a kick fails to cross the line of scrimmage or a player making a fair catch makes no effort to actually catch the ball.
Illegal crackback block by the offense: When an offensive player who lines up more than 2 yards laterally outside an offensive tackle, or a player who's in a backfield position at the snap and then moves to a position more than 2 yards laterally outside the tackle, clips an opponent anywhere. Moreover, the offensive player may not contact an opponent below the waist if the blocker is moving toward the position from which the ball was snapped and the contact occurs within a 5-yard area on either side of the line of scrimmage.
Illegal low block: When a player on the receiving team during a kickoff, safety kick, punt, field goal attempt, or extra point try blocks an opponent below the waist.
Piling on: When a ball carrier is helpless or prostrate, defenders jump onto his body with excessive force with the possible intention of causing injury. Piling on also results in an automatic first down.
Roughing the kicker: When a defensive player makes any contact with the kicker, provided the defensive player hasn't touched the kicked ball before contact. Sometimes this penalty, which also results in an automatic first down, is committed by more than one defensive player as they attempt to block a kick or punt.
Roughing the passer: When, after the quarterback has released the ball, a defensive player makes direct contact with the quarterback subsequent to the pass rusher's first step after the quarterback releases the ball. The NFL wants to protect its star players, so this penalty is watched closely.
Pass rushers are called for this penalty if they fail to avoid contact with the passer and continue to drive through or forcibly make contact with the passer. The defensive player is called for roughing if he commits intimidating acts such as picking up the passer and stuffing him into the ground, wrestling with him, or driving him down after he has released the ball. Also, the defender must not use his helmet or face mask to hit the passer. Finally, the defender must not strike the quarterback in the head or neck area or dive at his knees. Roughing the passer results in an automatic first down.
Taking a running start to attempt to block a kick: When a defender takes a running start from beyond the line of scrimmage in an attempt to block a field goal or extra point and lands on players at the line of scrimmage. This penalty prevents defensive players from hurting unprotected players who are attempting to block for their kicker.
Unnecessary roughness: This penalty has different variations:
Striking an opponent above the knee with the foot, or striking any part of the leg below the knee with a whipping motion
Tackling the ball carrier when he's clearly out of bounds
A member of the receiving team going out of bounds and contacting a player on the kicking team
Diving or throwing one's body on the ball carrier when he's defenseless on the ground and is making no attempt to get up
Throwing the ball carrier to the ground after the play is ruled dead (when an official has blown the whistle)
Hitting a defenseless receiver in one of the following ways: leaving one's feet and launching into the receiver or using any part of the helmet to initiate forceful contact
Unsportsmanlike conduct: When a player commits any act contrary to the generally understood principles of sportsmanship, including the use of abusive, threatening, or insulting language or gestures to opponents, officials, or representatives of the league; the use of baiting or taunting acts or words that engender ill will between teams; and unnecessary contact with any game official.