Actually, it depends. Is it a civil or criminal trial? If it's a criminal trial, and say Person A was tortured and revealed something, but Person B was being prosecuted, the evidence would likely be admissible against Person B, but not Person A (the one who was tortured). There is a legal reason for this but it is procedural (technical). If the person being tortured revealed something and someone wants to use it against him then in a criminal proceeding that would not be admissible. In a civil proceeding, the rules are a bit different, but I won't elaborate on those here.
