A Honolulu federal grand jury returned a 17-count indictment against a former prison guard, charging him with sexual abuse of three female inmates.

Mikael Salvador Rivera, 45, of Kapolei pleaded not guilty at his arraignment, held Thursday at Honolulu federal court, on charges of six counts of sexual abuse by threats and 11 counts of sexual abuse of a ward.

He was released on a $50,000 unsecured bond following his court appearance. Rivera’s trial is scheduled to be held in March.

He faces a maximum of life in prison for each count of sexual abuse by threats and up to 15 years in prison on each count of sexual abuse of a ward, if convicted.

Rivera could not be reached for comment.

Court documents said Rivera, also known as Sanny Salvador Rivera, was a correctional officer at the Federal Detention Center of Honolulu from 2014 to 2018.

The indictment alleged Rivera committed multiple sexual acts with one inmate through the use of threats while he was on duty in May 2018. It also alleged he engaged in sexual abusive conduct with another inmate around April 2017 through January 2018 and a third inmate around April 2018.

In a Wednesday news release, U.S. Attorney Clare Connors for the District of Hawaii said, “Government employees entrusted with the custody of inmates are responsible for the safety of both the community as well as of those inmates.”

“This prosecution holds a prison guard accountable for flagrantly and repeatedly violating the law and thereby failing to meet this responsibility,” she said.

In 2022 a $100,000 settlement was reached between Rivera and two former female inmates in a 2020 civil complaint. The women alleged Rivera sexually assaulted them in May 2018.

Rivera denied he sexually assaulted the two inmates, according to court records.

The women also alleged detention center staff retaliated against them after they reported the assaults.

Two prison officials and the federal government were later dismissed from the civil lawsuit.