A Northern Marianas Senator, Juan Ayuyu, pleaded not guilty to a new indictment charging him with obstructing justice.
It is alleged he threatened and tampered with witnesses and attempted to destroy evidence related to a case in which he is accused of attempting to smuggle federally protected fruit bats.
Federal agents arrested 48-year-old Mr Ayuyu on Monday.
The new charges include conspiring to obstruct an official proceeding, tampering with a witness, attempting to prevent the testimony of a witness, obstructing justice, and attempting to destroy or remove seized property.
Mr Ayuyu is under indictment for violating the Endangered Species Act and the Lacey Act for his role in allegedly possessing and transporting eight Mariana fruit bats from Rota to Saipan two years ago.
If found guilty he could be jailed for a year and receive a 25,000 US dollar fine for each offence.