Rules available at:

And on the official WFTDA YouTube channel:

Games are broken into units of play called “Jams,” which last up to two minutes. There are 30 seconds between each Jam.

During a Jam, each team fields up to five Skaters. Four of these Skaters are called “Blockers” (together, the Blockers are called the “Pack”), and one is called a “Jammer.” The Jammer wears a helmet cover with a star on it.

The two Jammers start each Jam behind the Pack, and score a point for every opposing Blocker they lap, each lap.

The Jammer is the only Skater who can score points for their team.

The first jammer that legally makes it through the pack on the initial pass is considered the “Lead Jammer”. The Lead Jammer earns the ability to call off a jam. Lead jammer is signaled by the ref’s arm pointing at the jammer.

Roller derby is a full-contact sport; however, Skaters cannot use their heads, elbows, forearms, hands, knees, lower legs, or feet to make contact to opponents. Skaters cannot make contact to opponents’ heads, backs, knees, lower legs, or feet.

Play that is unsafe or illegal may result in a Skater being assessed a penalty, which is served by sitting in the Penalty Box for 30 seconds of Jam time

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