Regardless of the whether your father-in-law needs to be put on a leash as your family believes, this is unethical if not illegal (at least in liberal parts of the world).
Unless he is a danger to himself or others, as determined by an independent professional, what is your family's justification for unilaterally deciding he should be banned from talking to people?
Unless he is a danger to himself or others, as determined by an independent professional, what is your family's justification for unilaterally deciding he should be banned from talking to people?