(1) Without prejudice to any other right to discovery, the Attorney General may, in proceedings for establishing a forfeiture under this Act, administer interrogatories to and obtain discovery of documents from a defendant as to any matter or document tending to prove that a person is an alien or to discover any land held by a person or in trust for that person as to any relevant matter or document.
(2) It is not a valid ground, to refuse to answer an interrogatory or to disclose or produce any document, that the answer or document might or would expose a person to the risk of prosecution under this Act.
(3) In the prosecution of a person under this Act, the fact that the person has disclosed a matter in answer to an interrogatory administered under this section and disclosed or produced any document in compliance with an order for discovery obtained under this section shall not be admissible in evidence.