The defense rested Friday in the manslaughter trial of a Baltimore police officer who testified he told his colleagues that Freddie Gray wanted to go to the hospital, but he saw no reason to call an ambulance for the prisoner.

Defense attorneys rested their case after calling 12 witnesses over three days, including the defendant, Officer William Porter.

Jurors were sent home for the weekend, but attorneys and the judge were to reconvene Friday afternoon.

Porter testified he spoke to Gray at two of six stops made by a police van that carried the prisoner in handcuffs and shackles. Porter said Gray indicated at the fourth stop he needed medical care, but the officer saw no obvious injuries. He testified he told the van driver and a supervisor that Gray wanted to go to the hospital.

Instead, Gray was taken to a police station, where he arrived unconscious and with a broken neck. He died a week later, on April 19.

Prosecutors say Porter was criminally negligent for failing to call a medic and failing to buckle Gray in with a seatbelt during the 45-minute trip.

Medical witnesses disagreed about where along the route the injury occurred, and whether it would have instantly rendered Gray unable to speak.

Witnesses on police procedure disagreed about whether Porter failed a duty to keep Gray safe. The prosecution's expert said Porter had a shared duty to follow department policies requiring seat belts for prisoners and medical care for those that request it.

A defense expert said Porter used good judgment in deciding not to buckle Gray in, thereby reducing the risk of the prisoner grabbing his gun. And he said Porter properly informed those ultimately responsible for Gray -- van driver Officer Caesar Goodson and Sgt. Alicia White -- that Gray should go to a hospital.

Gray was a 25-year-old black man arrested after he ran from police in his neighborhood. His death set off protests and rioting in the city, and became a rallying cry for the Black Lives Matter movement.

Porter, who is also black, is the first of six officers charged to face trial. His jury, seven women and five men, is considering four charges: manslaughter, assault, misconduct in office and reckless endangerment. He could face about 25 years in prison, if convicted on all charges.

The trial began Nov. 30.