Each team has up to five skaters on the track at once. One member of each team is designated as the point scorer, or jammer. She’s easy to keep track of because she wears a star on her helmet, and starts 20 feet behind the pack. The pack, through which the jammers must pass, consists of three blockers for each team, and one pivot for each team. The pivot wears a stripe on her helmet, and her job is to control the speed of the pack.
She can also, in a rare circumstance, take over from the jammer if the jammer decides to “pass the star” to her. She is the only player who can do this, and once she has done it she cannot switch back for the duration of the jam.
At the first whistle, the pack takes off and gets up to speed and into position: at the second whistle, both jammers take off and try to catch and lap the pack. The first one through the pack with no fouls or passes out of bounds is declared lead jammer, and can stop the action at any time by signaling to the refs. If neither one makes it through cleanly, there’s no lead, and the action must continue for the full two minutes. After the first lap, which is skated to determine lead, the jammer scores one point for each opposing team member she passes legally, in-bounds, without committing a foul. The action takes place during jams which last up to two minutes. The game is unusual in that all players must play offense and defense simultaneously, getting their jammer through the pack while stopping the opposing team’s jammer. Players engage by hitting, blocking, or pushing their opponents using their upper arms, shoulders, chests, or hips. Legal contact areas are the torso (excluding the lower back) and thighs– it is illegal to hit opponents in the head, lower legs, or back. Players cannot use their head, elbows, hands, forearms, legs, or feet to hit or push opponents.
Illegal moves will be called as fouls. Four minor penalties count as a major. (More serious fouls are immediately called as major penalties.) A major penalty means a player has to sit in the penalty box for a full minute, and her team cannot replace her, not even if she is the jammer or pivot.
Penalties extend beyond the end of jams, so teams must still skate short if there was a major assessed on one of their members in a previous jam: the offending player must sit in the penalty box, while her replacement in the next line-up stands beside the box waiting for the penalty time to expire.
The object of the game is for the jammers to pass the members of the opposing team. A jammer gets a point for each opposing blocker she passes, and an additional point for passing the opposing jammer. A jammer does NOT get a point if she commits a foul on a blocker, or passes a blocker out of bounds. Within these simple rules of engagement, there is room for a great deal of complicated strategy.
It is important to remember that, unlike the old-fashioned pro-wrestling-style roller derby on TV, modern amateur women’s flat-track derby is played for real. Everyone on the track is in it to win it.