This came up in the game last night, and there's not an obviously "right" answer.
This spell enables you or a creature you touch to move and attack normally for the duration of the spell, even under the influence of magic that usually impedes movement, such as paralysis, solid fog, slow, and web. All combat maneuver checks made to grapple the target automatically fail. The subject automatically succeeds on any combat maneuver checks and Escape Artist checks made to escape a grapple or a pin.
The spell also allows the subject to move and attack normally while underwater, even with slashing weapons such as axes and swords or with bludgeoning weapons such as flails, hammers, and maces, provided that the weapon is wielded in the hand rather than hurled. The freedom of movement spell does not, however, grant water breathing.
If a character has FoM active on him and jumps into a body of water, does he simply fall through the water as if it were air? If not, why not (and "a wizard did it" is not an acceptable answer ;) ?
The two ways I can read the second paragraph are either that "move and attack normally while underwater" means "as if not underwater", and thus the character would fall (and take falling damage as usual); or, it means "normally" as in the same thing that would happen without the FoM effect, which is absurd on its face since that's the entire purpose of the spell.
I can't see any sort of logic in this effect letting you move without resistance when you're walking, running, or swinging a weapon, but still letting you "swim" up and down.
With my current interpretation (character would fall), I would say that any effect that would normally prevent a fall or falling damage (Air Walk, Featherfall, Fly speed, etc) would work underwater as well as in air. The character with the FoM effect would also know (if he were the caster) how the spell works, and would have the option not to jump and fall, or to dismiss the effect first.
What say you?
Freedom of Movement does not mean that the character will automatically plummet to the bottom of a body of water, unless of course that is the character's desire. The text says move "normal" and if you go to the Underwater Combat section of the PRD you can see what "normal" means.
They do not have a penalty to hit or damage with slashing or bludgeoning weapons (or piercing for that matter), they do not have a penalty to movement (ie they can swim their normal land speed instead of half or quarter), and they are not off balance. If a medium character has more than 16 pounds of gear, then they can weigh themselves down and walk on the bottom. You may still require them to make a successful Swim check but the resulting movement would be full.
They don't have to automatically sink to the bottom as the water still provides buoyancy even if it does not provide the normal resistance to mevement.
Also, it seems that a character with Fly would be able to move through the water unhindered as well at the normal Fly speed while under the effect of a Freedom of Movement spell.
This is a good question. Freedom of Movement doesn't really make much sense if you think about it.
Even if the water did provide buoyancy like normal, wouldn't the friction you get moving your arms and legs to swim be negated by the FoM spell? How could you propel yourself forward to move if the water isn't giving you any resistance?
HA, I was playing Everquest 2 once and a "friend" cast a spell like this on me. Not knowing, I jumped off a dock and "fell" to the bottom and died.
I would rule that it allows you no detrement to your movements underwater but no hinderance either.