Official ( Canadian football ) An official in Canadian football is a person who has responsibility in enforcing the rules and maintaining the order of the game . Equipment . Canadian football officials generally use the following equipment : Uniform . For ease of recognition , officials are traditionally clad in a black - and - white vertically striped shirt , white knickers with a black belt , black shoes , and a peaked cap . Positions and responsibilities . Referee . The referee is responsible for the general supervision of the game and has the final authority on all rulings . Thus , this position is sometimes referred to as head referee and is considered to be the crew chief . He can be easily identified by his differently coloured cap . In the Canadian Football League ( CFL ) , the referee wears a black cap while the other officials wear white caps . In amateur football , including CIS football , the referee wears a white cap with black piping while the other officials wear black caps with white piping . During each play from scrimmage , the referee positions himself behind the offensive team , favouring the right side ( if the quarterback is a right - handed passer ) . He also counts offensive players . On passing plays , he primarily focuses on the quarterback and defenders approaching him . The referee rules on possible roughing the passer and , if the quarterback loses the ball , determines whether it is a fumble or an incomplete pass . On running plays , the referee observes the quarterback during and after he hands off the ball to the running back , remaining with him until the action has cleared just in case it is really a play action pass or some other trick passing play . Afterwards , the Referee then checks the running back and the contact behind him . During punt s and field goal s , the referee observes the kicker ( and holder ) and any contact made by defenders approaching them . In the CFL and other professional leagues , and in some CIS football games , the referee announces penalties and the numbers of the players committing them , and clarifies complex and / or unusual rulings over a wireless microphone to both fans and the media . During instant replay reviews in the CFL , the referee confers with a replay official , who is stationed in the press box above the field , on the play and then announces the final result over the wireless microphone . For replays in the CFL , the referee also views the play on a monitor stationed near the sidelines . In addition to the general equipment listed above , the referee also carries a coin in order to conduct the pregame ( and if necessary , overtime ) coin toss . Umpire . The umpire ( U ) stands behind the defensive line and linebackers , observing the blocks by the offensive line and defenders trying to ward off those blocks — looking for holding or illegal blocks . Prior to the snap , he counts all offensive players . During passing plays , he moves forward toward the line of scrimmage as the play develops in order to ( 1 ) penalize any offensive linemen who move illegally downfield before the pass is thrown or ( 2 ) penalize the quarterback for throwing the ball when beyond the original line of scrimmage . He also assists on ruling incomplete passes when the ball is thrown short . As the umpire is situated where much of the play ' s initial action occurs , he is considered by many to hold the most dangerous officiating position . In addition to his on field duties , the umpire is responsible for the legality of all of the players ' equipment . Head Linesman . The head linesman ( H or HL ) stands at one end of the line of scrimmage ( usually the side opposite the press box ) , looking for possible offsides , encroachment and other fouls before the snap . As the play develops , he is responsible for judging the action near his sideline , including whether a player is out of bounds . During the start of passing plays , he is responsible for watching the receivers near his sideline to a point 5 - 7 yards beyond the line of scrimmage . He marks the forward progress of the ball and is in charge of the chain crew in regard to its duties . In addition to the general equipment listed above , the head linesman also carries a chain clip that is used by the chain crew in order to properly place the chains and ensure an accurate spot when measuring for a first down . Line Judge . The line judge ( L or LJ ) assists the head linesman at the other end of the line of scrimmage , looking for possible offsides , encroachment and other fouls before the snap . As the play develops , he is responsible for the action near his sideline , including whether a player is out of bounds . He is also responsible for counting offensive players . During the start of passing plays , he is responsible for watching the receivers near his sideline to a point 5 - 7 yards beyond the line of scrimmage . Afterwards , he moves back towards the line of scrimmage , ruling if a pass is forward , a lateral , or if it is illegally thrown beyond the line of scrimmage . On punts and field goal attempts , the line judge also determines whether the kick is made from behind the line of scrimmage . Field Judge . The field judge ( F or FJ ) works downfield behind the defensive secondary on the same sideline as the line judge . He makes decisions near the sideline on his side of field , judging the action of nearby running backs , receivers and defenders . He rules on pass interference , illegal blocks downfield , and incomplete passes . He is also responsible for counting defensive players . He has sometimes also been the official timekeeper . With the back judge , he rules whether field goal attempts are successful . Side Judge . The side judge ( S or SJ ) works downfield behind the defensive secondary on the same sideline as the head linesman . Like the field judge , he makes decisions near the sideline on his side of field , judging the action of nearby running backs , receivers and defenders . He rules on pass interference , illegal blocks downfield , and incomplete passes . He also counts defensive players . During field goal attempts he serves as a second umpire . Back Judge . The back judge ( B or BJ ) stands deep behind the defensive secondary in the middle of the field , judging the action of nearby running backs , receivers ( primarily the tight ends ) and nearby defenders . He rules on pass interference , illegal blocks downfield , and incomplete passes . He covers the area of the field in between himself and the umpire . He has the final say regarding the legality of kicks not made from scrimmage ( kickoffs ) . With the field judge , he rules whether field goal attempts are successful . Other officiating systems . Junior football , high school football , and other levels of football have other officiating systems .