For the purpose of any investigation or proceeding under this chapter, the Director, or any officer designated by the Director, may administer oaths and affirmations, subpoena witnesses, compel their attendance, take evidence, and require the production of any books, papers, correspondence, memoranda, agreements, or other documents or records which the Director deems relevant or material to the inquiry. The Director's authority to subpoena witnesses and documents outside the State shall exist to the maximum extent permissible under federal constitutional law.