The 20-year-old man charged in connection with the brutal slaying of an American University graduate on a crowded Metro train nearly two years ago is criminally responsible, doctors at the District’s psychiatric hospital determined this week.

During a hearing Friday in D.C. Superior Court, Judge Judith Bartnoff read parts of a 72-page report authored by psychiatrists at St. Elizabeths Hospital. They determined that although the suspect, Jasper Spires, may have suffered from mental illness at the time he allegedly stabbed 24-year-old Kevin Sutherland on July 4, 2015, the illness was not so severe that it should have prevented him from conforming his behavior. And, they determined, Spires is now competent to assist in his own defense.

Prosecutors said that Spires, who is charged with first-degree murder, stabbed Sutherland as Spires tried to rob him of his cellphone. The horrific attack shocked the District as about a dozen Metro passengers en route to enjoy holiday festivities in the nation’s capital watched the assault unfold. The attack occurred around 1 p.m. during an estimated three-minute ride as the Red Line Metro train passed between the Rhode Island and No-Ma/Gallaudet Metro stations.

Court documents said Sutherland was cut or stabbed 30 or 40 times in the chest, abdomen, back, side and arms. Police said Spires then threw Sutherland’s cellphone and returned to stomp on Sutherland’s body.

[Horrified passengers watch brutal slaying on Metro train]

Spires initially was represented by an attorney who said his client was not involved in the attack. Spires then hired attorneys from the District’s Public Defender Service, who argued that their client was mentally incompetent and requested multiple psychological evaluations.

In 2015, just three months after his arrest, doctors at St. Elizabeths determined that Spires was competent. Prosecutors later requested additional evaluations.

[Suspect in July 4 fatal stabbing of American University graduate found competent]

A week after his arrest, Spires showed bizarre signs of behavior in the courtroom as he laughed and interrupted a judge.

But in court Friday, Spires was mostly quiet, saying, “Good morning” to the judge, then asking her, “How are you doing?”

Bartnoff tentatively set the trial for May 2018. Spires’s public defenders said that they may need more time to review their client’s latest psychological evaluation before they determine their next step, including pursuing an insanity defense. Attorneys said that they expect the trial to last about a month. Prosecutors said that at least three people who they say also were attacked on the train by Spires are expected to testify at the trial.

Sutherland’s parents and other family members filled nearly two rows of the courtroom Friday. Doug Sutherland, his father, said the family was pleased with the doctors’ findings. He said the family believes the attack was “calculated.” “He was in control of his actions,” Sutherland said.

But while wearing a lapel pin that displayed his son’s picture, Sutherland said it would be difficult to wait at least another year before the case goes to trial.

“I knew the wheels of justice were slow, but I didn’t know they would grind this slowly,” he said.