Each team has one scoring position, the Jammer. Jammers are designated by a star worn on their helmet and they start behind the other skaters (the pack).
The other positions on each team are blockers. Eight blockers, four from each team, make up the pack.
Pivots are designated by a stripe worn on their helmets. They can become a jammer for their own team by a move known as passing the star.
How it Works
Five skaters from each team are allowed on the track at once. Skaters move in a counter-clockwise direction.
Each team has one scoring position called the "JAMMER". Jammers are designated by a star worn on their helmet and start behind the other skaters.
The eight blockers, four from each team, make up the "PACK". When the first whistle is blown, the pack, led by the pivots, begins to skate.
Jammers begin to skate when the second whistle blows. Jammers then try to make their way through the pack. Blockers try to keep the opposing jammer from getting through while simultaneously trying to help their own jammer.
On the first pass through the pack, the first jammer to pass each member of the pack WITHOUT FOULING becomes "LEAD JAMMER". A referee will point to the lead jammer as she skates to designate her status.
Lead jammer has the strategic advantage of calling off the "JAM" at any time by placing her hands on her hips.
Jammers score points by passing members of the opposing team, while remaining in bounds, on their SECOND time through the pack and every pass thereafter. A jam lasts a maximum of two minutes, or until the lead jammer calls it off.
Why is she lead?
Under WFTDA "any pass" rules, a jammer is eligible to become lead jammer as soon as they pass each player in the pack legally. Even if they make a bad pass, she can remain in the pack and try to pass that player legally--and as soon as it's clean, it counts! So a smart jammer who wants a strategic advantage might fall back and re-attempt a pass.
WHAT HAPPENS IF NO ONE GETS LEAD JAMMER?
The first time through the pack, if both jammers make "unclean passes" (by fouling or stepping out of bounds while passing a blocker) there is no lead jammer and the jam will continue for the full 2 minutes. This can wear the jammers out--so most hate it when it happens!
HOW DOES A JAMMER GET POINTS?
Jammers begin to accrue points on their second pass through the pack. They receive one point for every opposing player they pass. They also receive points for any players in the penalty box, but only after they have cleared the pack. On the flip side, jammers will not be awarded points if they foul the opposing player they are passing or if either of their skates steps out of bounds while passing that opposing player. REMEMBER...jammers may re-pass players to get points.
If a jammer laps the opposing team's jammer, they score an extra point. This is called a "grand slam" and is worth five points.
If a skater earns a penalty they will immediately be sent to the penalty box to serve 30 seconds. If a skater earns 7 penalties in a single game, they are said to have "fouled out" and are expelled from the game. A skater may be ejected from the game for a single action if it is deemed by the officials staff to be egregious or too unsafe for play.