There is a word/phrase that I can't recall that is bothering me. It means to be able to take responsibility for a situation or to have the ability to control ones actions.
For example, if you "take away someone's ____________________" in a legal or societal sense, you remove their responsibility for themselves. Minors are considered not to have this thing, and slaves/people incarcerated would also be considered to not have it.
What is this word/phrase I'm thinking of?