A Maryland court of appeals postponed the trial of Caesar Goodson Jr., the police van driver who has been linked to the murder of Freddie Gray. He has been charged with second-degree murder. Amid the process of jury selection, the trial was delayed on Monday in order for the Maryland Court of Special Appeals to determine whether another Baltimore officer can be ordered to testify against Goodson.

The decision follows a series of legal filings in which William Porter protested a Circuit Court judge's order to compel him to testify against the accused. Circuit Judge Barry G. Williams appeared in court briefly on Monday to announce the appeals court stay and put Goodson's trial on pause.

Williams added that the prosecution had asked for a continuance. The request however, was "moot" considering the appeals court stay, according to the Baltimore Sun.

Freddie Gray's death, resulting from a violent trip in a police van, sparked massive protests in Baltimore and drew support for the Black Lives Matter movement.

While prosecutors have kept their case under wraps, they revealed last week in a pretrial hearing that they planned to call a witness specializing in "retaliatory prisoner transport practices," according to the AP.

The defense's action has double meaning: the witness they referred to in the pretrial is former Baltimore police officer and Maryland state trooper Neil Franklin. The defense attorneys argued during the hearing that prosecutors had employed, "a new legal theory or area of testimony at the proverbial eleventh hour," reported NBC.

The defense, therefore, seeks to block the testimony of both Porter and Franklin. At Porter's own trial, he stated he had travelled with Gray for the majority of the 45 minute car ride in which he was injured. He attributed Gray's death to the fact that he did not secure his seatbelt.