A 19-year-old charged with murdering his girlfriend's grandparents could face the death penalty, Gwinnett County District Attorney Danny Porter said.

Johnny Hiro Rider and Cassandra Bjorge were both indicted on murder, aggravated assault, aggravated battery, armed robbery and theft charges in connection with Bjorge’s grandparents’ death. Randall and Wendy Bjorge were bound with duct tape, beaten with a tire iron and stabbed before Rider and Cassandra Bjorge slit their throats, police said.

Rider and Bjorge also beat Rider's sister with a baseball bat, kicked the sister's boyfriend's front teeth out and stole Rider's mother's car, the indictment alleges. The alleged assault left Rider's sister with seven staples in her head.

The indictment of Bjorge and Rider was returned by a grand jury around 3:45 p.m. Thursday.

The district attorney’s office is “considering” seeking the death penalty for Rider, Porter said. They cannot seek the death penalty against Bjorge because she is 17 years old. Defendants must be 18 to be eligible for the death penalty.

After Bjorge and Rider killed Bjorge's grandparents, the couple caulked the doors of the grandparents' Lawrenceville home to hide the stench of decaying bodies as they partied with friends downstairs, a Gwinnett County detective testified at a hearing shortly after the couple's arrest. The two allegedly killed the grandparents because they had gotten "too strict," the detective testified.

They also had a “hit list” containing multiple members of Bjorge’s family, the detective said.

Bjorge and Rider attempted to kill themselves during a SWAT standoff with police before they were arrested in April. They have been held in the Gwinnett County Detention Center without bond since April 11.

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