Speaking is a free action, but it doesn't specify wether it can be done on your turn or not, unlike an immediate action. Can you speak when you are being attacked for instance?
Lets say I have a contingent spell that I want to go off, protection from evil for simplicities sake, linked to a command word, smock for instance(because I like that word)
-Can I say the command word during other peoples turns?
-Can I say the command word in response to being dominated? (before making a save but after the spell is cast)
-Can I say the command word when I'm flat-footed?
-Would saying the command word in an area of silence actually stop the contingency?
(because the contingency is me saying the word, not that it actually makes sound when I say it)