District Attorney Martha Coakley had said earlier in the week that Colono did not have a criminal record. LaGrassa declined to comment yesterday on the victim’s criminal record.

Meanwhile, Denner said Pring-Wilson underwent a polygraph test yesterday agreed upon at Monday’s arraignment.

Denner said his client will likely undergo medical and psychological evaluations today as evidence for tomorrow’s bail hearing.

Denner also said he is collecting letters from Pring-Wilson’s friends, family and professors which he will submit to the court.

According to investigators’ accounts, released Saturday by the district attorney, Pring-Wilson was walking home from a nightclub alone sometime after 1 a.m. when he encountered Colono, 18, sitting in a car with Rodriguez and Abreu.

Investigators say Colono got out of the car, and a violent fight between Pring-Wilson and him ensued, leaving Colono with five stab wounds to the torso.

Emily LaGrassa, a spokesperson for the Middlesex County District Attorney, said Colono and friends left the scene not realizing he had been stabbed.

Colono was pronounced dead at the Beth Israel Deaconess Medical Center later that morning.

Colono was raised and attended school in Cambridge, and worked at a local Days Inn. He leaves a three-year-old daughter, who is being raised by her mother.

Pring-Wilson, a Colorado native, planned to receive his Master’s degree this spring, and then return to Colorado for law school.

—Hana R. Alberts contributed to the reporting of this story.

—Staff writer Jenifer L. Steinhardt can be reached at steinhar@fas.harvard.edu.