In roller derby, two teams compete against each other on an oval-shaped track. The players skate on four-wheeled quad roller skates. The object of the game is to score more points than the opposing team. Each team has four blockers and one jammer on track. Jammers score points by lapping opposing blockers on the track and blockers try to stop the opposing jammer from passing while helping their own jammer to pass the opponents.
Roller derby is a full contact sport with roots in the 1920’s U.S.A. Contemporary roller derby started in Austin, Texas in 2001 and has since become one of the fastest growing women’s sports.
A roller derby game consists of two 30-minute periods. Each period is composed of an unlimited number of ‘jams’ which can last up to two minutes. After each jam, the teams have 30 seconds to line up for the next jam. The blockers start the jam between the pivot line and the jammer line. Jammers start behind the jammer line. The jam starts with one long whistle and ends when four short whistles (repeated three times) are blown. The jam ends either when the lead jammer makes the call-off signal by placing their hands on their hips repeatedly, or when two minutes is up on the jam clock. The jam can also be whistled dead for a number of reasons, e.g. one team hasn’t fielded a jammer or any blockers when the jam starts.
There has to be two teams on the track for a jam to start or continue; meaning there has to be at least one blocker and one jammer from each team on the track. The team roster consists of up to 15 skaters. Each team can have no more than five skaters on the track at one time. A full line-up is made up of four blockers and one jammer. The jammer is the only person who can score points. One of the blockers can be designated pivot, which means they are eligible to receive the jammer status from the original jammer. A pivot wears a striped helmet cover, while the jammer is designated by a helmet cover with a large star on both sides. Blockers do not wear helmet covers.
The jammers score points by passing the opposing team’s blockers. A pass is made when the jammer’s hips pass the opponent’s hips. The scoring must be done in-bounds and legally. The blockers work together to help their jammer through the pack while preventing the opposing jammer from scoring points. This includes moving opposing blockers out of the way, assisting their jammer, and blocking the opposing jammer. The first time the jammers skate through the pack of blockers, called the ‘initial pass’, the jammers are not scoring points, but competing for the ‘lead jammer’ status. The lead jammer is the first jammer who makes it through the pack, while having passed all the opposing blockers legally and in-bounds. The lead jammer status is a strategic position; they can call off the jam before the two minutes is up if it’s beneficial for their team. If the lead jammer receives a penalty or if they pass the star to their pivot, they and their team lose the lead jammer status.
The blockers from both teams are responsible for the pack formation at all times. The pack is defined by the largest group of upright and in-bounds skaters from both teams within 3-feet distance from each other. If the pack can’t be defined, and there’s a no-pack situation, the blockers must reform the pack as soon as possible. The blockers are not allowed to have an impact on the game in a no-pack situation. When the pack is defined, the blockers can move and play offence or defence in the pack, or in the 6 meters engagement zone in front of the foremost pack skater or behind the last pack skater. The jammers are not part of the pack, so they can engage each other anywhere on the track.
If a skater receives a penalty, they are sent to the penalty box to serve 30 seconds for the infraction. This includes bettering their team’s position by e.g. cutting the track, impeding or grabbing the opponent with hands/forearms, blocking someone in illegal target areas (above the shoulders, in the back, below the mid-thigh), blocking someone with illegal blocking areas (head, elbows, hands, below mid-thigh), blocking a jammer while 6 meters ahead or behind the pack, making contact while out-of-bounds, stopped or clockwise blocks etc. If the skater doesn’t leave the track when sent out to serve their penalty, the referee can give them an extra 30 seconds penalty for insubordination. If a skater receives seven penalties during a game, they foul out. The Head Referee can also expel a skater for a gross misconduct.
In addition to a group of non-skating officials, there are seven referees officiating the bout, skating both on the inside and on the outside of the track. Both jammers have a referee who skates by the jammer’s side and all the other referees watch the action in the pack. One of the referees is the Head Referee, who is the highest official in a bout.
The complete rule set can be found here.