The suspect made his initial appearance in Boone County Superior Court on Friday morning dressed in an orange jail jumpsuit and a bulletproof vest.
Richard Allen was convicted in November in the killings of 13-year-old Abigail Williams and 14-year-old Liberty German.
Joseph Corcoran has been on Indiana's death row since his 1999 conviction in the fatal shootings.
Brett Hankison's actions in Breonna Taylor raid were 'unfathomably dangerous,' officers will testify
Hankison believed there was someone with a rifle "executing his friends,” his attorney told jurors. “Brett Hankison did everything he could to try to protect and save his fellow officers."
Ashlea Hellmann, a defense attorney and former public defender in Louisville, was charged with felony trafficking in synthetic drugs and promoting contraband.
The remains of U.S. Army Pfc. Thomas Franklin Brooks were flown to Louisville on Thursday.
In court Friday, defense attorney Rob Eggert entered a not guilty plea for Christopher Lee Gordon, Sr.
A community's worst fear was realized Thursday when Jefferson Circuit Court Judge determined that Cane Madden is mentally incompetent to stand trial.
The judge's decision on Cane Madden's mental competency is expected next week.
Madden has already been found incompetent to stand trial in several previous criminal cases, including by the judge handling his current case.