SECTION 30 BRIBERY OR CORRUPT SOLICITATION. The offense of corrupt solicitation of members of the legislature, or of public officers of the state or any municipal division thereof, and any occupation or practice of solicitation of such members or officers to influence their official action, shall be defined by law, and shall be punished by fine and imprisonment. Any person may be compelled to testify in any lawful investigation or judicial proceeding against any person who may be charged with having committed the offense of bribery or corrupt solicitation, or practice of solicitation, and shall not be permitted to withhold his testimony on the ground that it may criminate himself or subject him to public infamy, but such testimony shall not afterwards be used against him in any judicial proceeding - except for perjury in giving such testimony - and any person convicted of either of the offenses aforesaid, shall as part of the punishment therefor, be disqualified from ever holding any position of honor, trust or profit in this state. A member who has a private interest in any bill or measure proposed or pending before the legislature, shall disclose the fact to the house of which he is a member, and shall not vote thereon.