Use immunity allows the state or federal government to prosecute a witness using evidence obtained independently of the witness's immunized testimony. The state or federal government is prohibited from derivative use of immunized testimony for the prosecution of the immunized witness. The state or federal government must prove that the evidence is based upon an independent and legitimate source in order to prosecute the immunized witness. The state or federal government has to prove that the evidence came from a legitimate source independent from the compelled testimony.
