A militia was a military organisation.
Lei-Fang was the head of the Black Flag militia in 19th century China. (PROSE: The Eleventh Tiger)
Sergeant Stewart was in a militia force under the control of Graham Mackenzie, who once had Jamie McCrimmon in his squad. (PROSE: The Indestructible Man)
The Vogans were led by a High Council, which had their own militia that defended the centre of the planet of Voga. (PROSE: Doctor Who and the Revenge of the Cybermen)
Tobias Vaughn bribed the Oolian militia to kill Homeless Forsaken. (PROSE: Original Sin)
The Special Congress sent Jake McCrimmon with a militia unit to survey the aftermath of the Carnival Queen's return in Woodwicke. (PROSE: Christmas on a Rational Planet)
The Interior Defence Unit was a militia established by President Rassilon using the Drylands Precedent. It had the power to arrest any Time Lord on Gallifrey. (AUDIO: Havoc)