Baltimore(CNN) Baltimore police Officer William Porter will have to testify in the cases of two other officers facing charges in the death of Freddie Gray, a judge ruled Wednesday.
Judge Barry Williams ordered Porter to testify in the trials of Officer Caesar Goodson Jr. and Sgt. Alicia White, under limited immunity granted by prosecutors.
Porter's attorneys, who argue that forcing him to testify in the other cases would violate his rights, said they will file an appeal.
Porter was the first of six officers to go on trial in the closely watched case involving Gray, a 25-year-old detainee who suffered a fatal neck injury in April after being shackled and placed without a seat belt in a police van. Gray's death set off citywide demonstrations and calls for justice.
After jurors deadlocked, a mistrial was declared in Porter's trial last month. Porter is scheduled to face a retrial in June.
In compelling Porter to testify under this limited immunity, prosecutors can't use the officer's testimony in the Goodson and White cases, or anything learned from that testimony, against Porter when his own case is retried.
Porter's legal team argued there was no way the state could guarantee that information from Porter's testimony in other cases wouldn't be used against him later.
Baltimore officers in Freddie Gray case
Six Baltimore police officers were charged in the April 2015 death of Freddie Gray, who died of a severe spinal-cord injury while in police custody. But there were no convictions in the case. Three of the officers were acquitted before
prosecutors dropped the charges against the remaining three in July 2016. Seen here is
Lt. Brian Rice, who was part of the bike patrol that arrested Gray. On July 18, 2016, Rice was found not guilty of involuntary manslaughter, reckless endangerment and misconduct in office in connection with Gray's arrest and death.
Officer
Caesar Goodson drove the van in which Gray was fatally injured. On June 23, Goodson
was found not guilty on all charges, including the most serious count of second-degree depraved-heart murder.
William Porter was the first of the six officers to face a trial. It
ended in a mistrial in December, and he had been scheduled to be retried before prosecutors dropped the charges against him. Porter was summoned by the van's driver to check on Gray during stops on the way to a police station. Prosecutors said Porter should have called a medic for Gray sooner than one was eventually called, and they said he also should have ensured that Gray was wearing a seat belt. Porter had been charged with involuntary manslaughter, second-degree assault, reckless endangerment and misconduct in office.
Edward Nero, one of three bike officers involved in the initial police encounter with Gray,
was found not guilty of all charges in May. He was accused of second-degree intentional assault, two counts of misconduct in office and reckless endangerment.
Garrett Miller was another one of the bike officers involved in Gray's arrest. He placed Gray in a restraining technique known as a "leg lace" before Gray was placed in the van, said Marilyn Mosby, the state's attorney for Baltimore. All charges were dropped against Miller, who had been indicted on charges of second-degree intentional assault, two counts of misconduct in office and reckless endangerment.
Sgt. Alicia White was present during one of the stops to check on Gray's condition. She and two other officers saw Gray unresponsive on the floor of the van, and when White spoke to Gray and he did not respond, she allegedly did nothing to help him, prosecutors said. All charges were dropped against White, who had been indicted on charges of involuntary manslaughter, second-degree negligent assault, misconduct in office and reckless endangerment.
Jury selection in the trial of Goodson, who drove the transport van carrying Gray, is set to start on Monday.
CNN's Catherine E. Shoichet and Eliott C. McLaughlin contributed to this report.