At a pretrial hearing yesterday, several witnesses testified on the mental and physical health of a Harvard graduate student around the time of his arrest, after he allegedly killed a local teenager last April.

The hearing will continue today, when Judge Charles M. Grabau may decide whether to permit alleged lies Alexander Pring-Wilson told police on the night of his arrest as evidence.

Pring-Wilson, a student at Harvard’s Davis Center for Russian and Eurasian Studies at the time of his arrest, is charged with stabbing 18-year-old Michael Colono to death on April 12, 2003 after an early morning altercation outside of Pizza Ring, a local pizza parlor on Western Avenue.

Pring-Wilson’s attorney Jeffrey A. Denner said his client acted in self-defense.

On Feb. 23, Denner filed a motion in Middlesex Superior Court claiming Pring-Wilson was suffering from a concussion and post-traumatic stress disorder at the time of his arrest, and therefore the statements his client made to police and friends “were not knowing, intelligent or voluntary,” which they must be in order to be admitted as evidence.

The motion argued that Pring-Wilson was unfit to recount events accurately, and his statements from that night should therefore not be presented at his trial, scheduled for June 3.

In her questioning yesterday, Assistant District Attorney Adrienne Lynch tried to convince Judge Grabau, who will be ruling on Denner’s motion, that Pring-Wilson’s ability to make accurate statements the night of his arrest was intact.

Before the hearing began yesterday, Lynch filed the prosecution’s written response to Denner’s motion.

Lynch called 11 witnesses yesterday—including police, fire and medical personnel. She asked about Pring-Wilson’s behavior and claims of head pain in the day and a half after his arrest.

Lynch’s first witness was Christopher Nellis, the state police dispatcher who answered Pring-Wilson’s cellular 911 call at around 1:50 a.m. on the night of the stabbing.

According to a tape recording of the 911 call, which was played in court yesterday, Pring-Wilson—contrary to the argument he acted in self-defense—told dispatchers he had witnessed a stabbing.

Nellis said when he called Pring-Wilson back to confirm the 911 call, Pring-Wilson only responded, “911 is a great thing.”

Nellis routed the call to Cambridge 911 dispatcher Michael Ferraro, another witness yesterday, who said that Pring-Wilson told him he denied seeing the stabbing.

Cambridge Police Department (CPD) officer Donald Mahoney, who responded to the 911 call, said that Pring-Wilson didn’t appear to be incapacitated.

“He said he just observed a stabbing and an individual had run off,” Mahoney said yesterday at the hearing.

Mahoney noted Pring-Wilson kept putting his hand to his forehead, but he didn’t see any marks there.

Pring-Wilson had no trouble answering questions and didn’t ask for medical assistance, Mahoney said.

But Denner said his client had a different take on the encounter with Mahoney.

“The defendant was positive that he was beaten quite badly,” Denner said. “Because of the beating he was suffering from traumatic brain injury.”

CPD officer Robert Leary responded to the scene with Mahoney and testified that though Pring-Wilson was excited, he did not appear to be severely injured.

“From my vantage point I couldn’t see any cuts or bruises or contusions or anything,” Leary said.

Leary said he and Mahoney were trying to determine the whereabouts of the victim, so he did not focus on Pring-Wilson’s physical well-being or sobriety.

Richard Ma, the last witness called yesterday, was a resident at Cambridge Hospital last April and examined Pring-Wilson when he was brought in from the police station on the day of his arrest and the following day.

Over Denner’s objection that Ma was insufficiently qualified to give expert testimony on Pring-Wilson’s state of mind, Ma opined that Pring-Wilson suffered “no obvious head injury.”

Ma testified that, although Pring-Wilson complained of trauma, he did not display any physical signs of head injury on either day that Ma examined him.

“Before I touched him, he almost seemed like he was in pain,” Ma said. “The exam doesn’t coordinate with what the patient was saying.”

Ma also said that Pring-Wilson changed his story about whether he lost consciousness after being hit and kicked in the head during the incident. Pring-Wilson said on April 12, 2003 that he was not knocked out, but then said the next day that he lost consciousness for several seconds.

Ma conceded on cross-examination, however, that Pring-Wilson may have misinterpreted his question about his consciousness during his April 12 visit.

After hearing that Pring-Wilson had lost consciousness during the incident, Ma said he ordered a computed tomography (CT) scan of Pring-Wilson’s head, which turned up negative, indicating that Pring-Wilson did not suffer an internal head injury.

When Denner asked Ma why he did not follow up with an magnetic resonance imaging test (MRI), Ma said it was not an appropriate test for Pring-Wilson’s case.

CPD officer James M. Green, who also responded to the 911 call, testified that he noticed that Pring-Wilson had a dime-sized welt on his forehead.

Pring-Wilson said on the scene that he had witnessed a fight and he had intervened to help, Green said.

Green said Pring-Wilson appeared confused when asked which direction the victim and assailants had gone.

Green said Pring-Wilson refused medical help.

“He didn’t want to be bothered,” said Green.

Green also said Pring-Wilson told him he drank one or two beers that night, but the alcohol didn’t seem to affect his behavior noticeably.

“He appeared sober,” Green said. “He wasn’t slurring words or anything. He didn’t seem impaired by alcohol or physical injury.”

Cambridge Fire Department Captain Steven Boyle, a certified emergency medical technician for 30 years, noticed that Pring-Wilson had a lump on his forehead.

Boyle said he observed that Pring-Wilson had no problem standing or walking and denied losing consciousness, though in the motion to suppress Denner argued that Pring-Wilson did lose consciousness during the incident.

Boyle said from his experience it did not appear to him that Pring-Wilson suffered a serious head injury.

“What was obvious to me was the lump on his forehead,” Boyle said. “I would not refer to it as head trauma.”

However, Denner pointed out that in a report Boyle had written, he did in fact refer to Pring-Wilson’s injury as head trauma.

Boyle added that some of Pring-Wilson’s answers were garbled at the scene.

“I just couldn’t understand what he was saying,” Boyle said. “It sounded like he was trying to choose his words.”

Denner asked Boyle if he thought Pring-Wilson’s behavior in general was out of the ordinary.

“He seemed off somehow, didn’t he?” Denner asked.

“Yes,” Boyle confirmed.

Yesterday afternoon, Lynch called to the witness stand the four emergency medical technicians who took Pring-Wilson from the police station to Cambridge Hospital when he started to complain of head pain the afternoon after his arrest.

Robert Kallen and Alexei M. Wagner testified that they took Pring-Wilson to Cambridge Hospital on April 12, 2003, when he first complained of head pain, and Kathleen Ahern and Joseph Johnson said they took him the next day, when he allegedly said his condition had worsened.

All four EMTs said that Pring-Wilson was behaving normally and cooperated with them on both days.

When Denner asked about the brief examinations they conducted in the police station before taking Pring-Wilson to the hospital on both days, none of the EMTs said they saw external signs of injury.

But Ma, the physician, testified that Pring-Wilson had several superficial lacerations.

The rest of the motion’s witnesses, including psychiatric and medical experts, are scheduled to testify today, and the hearing will continue next week if necessary.

On Feb. 24, Denner filed a motion to move the trial to western Massachusetts, claiming that a Cambridge jury is likely to be biased because of the case’s extensive media coverage.

Judge Grabau said yesterday he will hear arguments on this motion after he rules on the current motion to suppress evidence.

—Staff writer Hana R. Alberts can be reached at alberts@fas.harvard.edu.

—Staff writer Joshua D. Gottlieb can be reached at jdgottl@fas.harvard.edu.