Section 6303 provides for the rights of parties in interest to an investigation by allowing them to be represented by counsel, to cross examine witnesses, and to call witnesses. This section merely states the rights of a party in interest but does not necessarily determine who is to be considered a party in interest. Clause (4) states that these rights are to be afforded to "any other person whose conduct is under investigation" (emphasis added). This implies that clauses (1) through (3) apply to individuals whose conduct is under investigation. If any individual does not qualify for these rights under clauses (1) through (4), that individual can still be entitled to these rights under clause (5), if designated as a party in interest. Since parties in interest are not clearly set out by statute, the Secretary has the authority to do this by regulation under section 6301. Thus the rights of these parties as presently provided for in existing law have been retained.