The letters on a ref’s jersey help designate what particular job has been assigned to that official. The seven positions are: Referee (R), Down Judge (DJ), Side Judge (SJ), Back Judge (BJ), Field Judge (FJ), Line Judge (LJ), and Umpire (U).
Even when I played football, I never paid much attention to the officials and what their exact jobs were. But understanding the different roles they have and how it allows them to work as a single cohesive unit has helped me understand how they officiate a game, and how challenging their job can be.
Let’s take a look at the various positions on an officiating crew including who’s in charge, where they line up before the snap, and what their job entails once the play begins.
- There are seven independent roles on an NFL official’s crew and the letters help distinguish between the different jobs.
- The Referee serves as the team’s captain and wears a white hat and an “R” on his uniform.
- The other positions are placed in strategic locations on the field to cover as much area as possible.
The quarterback of the officiating crew, the referee announces penalties and other calls over the loudspeaker and is considered the leader of the team. 
The referee lines up 10-12 yards behind the line of scrimmage and his primary responsibilities are to make sure that both teams only have 11 players on the field along with administering most roughing the passer penalties. 
He is designated by other members of the officiating team with a white hat as opposed to a black one.
He is designated with the letter “R” on his uniform and is the most recognizable of the officials with some of them becoming as notable as some players. Some like the retired Ed Hochuli and his massive biceps were easily recognizable whenever he was officiating.
The down judge, designated with a DJ, is in charge of the chain crew that measured down and distance. Along with directing the “chain gang” the Down Judge also watches for offsides infractions and any potential penalties that take place near the sideline. 
Assigned in the defensive backfield, the side judge wears an SJ on their uniform. Along with the field judge and back judge, they have the challenging job of determining penalties down the field on passes such as pass interference. They’re also responsible for deciding whether a not a ball is caught or not, a ruling that has brought about a lot of discussion and controversy in recent years. 
Deep behind the defensive secondary, the back judge wears a BJ on their uniform. Before the snap, they’re responsible for monitoring the play clock and raising their hand with ten seconds remaining to let the offense know that time is running out. 
Once the ball is snapped, they help officiate deep passing plays and can call pass interference, defensive holding, and whether or not a ball was caught.
Like the side judge, field judges are placed on the defensive side of the football, usually about 20 yards from the line of scrimmage. Their primary responsibility is to monitor the sideline catches along with trailing the play and determining if a player has scored a touchdown. They wear an FJ on their jerseys. 
Placed at the line of scrimmage on the opposite side of the down judge, the line judge wears an LJ on their uniform. They have similar responsibilities as the down judge, monitoring for offsides and false start infractions along with plays that take place near the sidelines. 
The umpire sits in the middle of the field between the linebackers and the secondary, usually about ten yards from the line of scrimmage. They have the challenging role of watching for holding penalties and other infractions that take place between the linemen and the contested area over the middle of the field. They wear a U on their uniforms. 
The diverse lettering on a referee’s uniform helps players, coaches, and fans identify the official’s specific role in the game. Like the teams, officials have to work together as a group and rely on each other to enforce a rulebook that can be extremely complex and follow a game that moves at a blazing-fast pace.
Would you ever want to be an NFL ref? If so, what job do you think you would be best at? Let us know in the comments below.
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