Standard SCA(USA) rules are that armoured archers are no longer considered to be light fighters. Everyone on the battlefield must be armoured to Society/Kingdom standards for Heavy Fighters. Anyone who doesn't wish to be physically struck can enter the field as a "Non-Contact", to designate this they place a Red Pheon on all four sides of their helm and are considered dead either by a touch of a weapon or by a Heavy Fighter with a Melee Weapon coming a certain distance to them(usually 10 feet) depending on each Kingdom's Law. Combat Archers are permitted to shoot blunt arrows at both heavy fighters. They are required to comply with Society heavy armour standards and use a bow with a maximum poundage of 30lb at 28 inches pull or a crossbow. Crossbow limits vary by Kingdom. All Combat Arrows for SCA(USA) events must have an Anti-Penetration Device or APD which prevents an arrow from entering a standard helm grill if it should strike a fighter after bouncing back or gets flipped in mid-flight. Some Kingdoms still allow [light] archers on the field but more [Kingdoms] are moving toward doing away with [light] archers and non-combatants on the field with [heavy] fighters.
Some [Kingdoms] allow Combat Archery on [Rapier] battlefields if the Marshal-in-Charge allows it in the scenario. Most that do allow it limit the number of archers on the field and require that Archers also be [Rapier] authorized also.
In Lochac armoured archers are considered to be light fighters, and are permitted to shoot blunt arrows at both heavy fighters and fellow light fighters. They are required to comply with Society light armour standards and use a bow with a maximum poundage of 30lb at 28 inches pull.