[Suicide Junkie]

Losing bridge (& aux bridge) in combat: lose half your movement.
Lacking bridge outside combat: lose half movement.
Losing crew quartes: lose half movement.
Losing lifes support: lost 75% of your movement.

These are all multiplicative, so losing bridge and crew quarters has the same effect as losing lifesupport.

If a ship has lost all three, 32 movement points get reduced to 2 MP. (anything less than 32 leaves 1MP)