The state’s highest court today affirmed the four first-degree murder convictions handed down two years ago for the fatal shootings of Jason Bachiller, Jihad Chankhour, Edwin Duncan, and Christopher Vieira during the robbery of three firearms in the basement of a Bourneside Street home, Suffolk County District Attorney Daniel F. Conley said today.

CALVIN CARNES, Jr. (D.O.B. 8/8/86) was convicted of all charges after two and a half weeks of trial during the summer of 2008 featuring 65 witnesses and more than 200 physical exhibits. In addition to finding him guilty of the murders, jurors also convicted Carnes of three counts of armed robbery, two counts of unlawful possession of a firearm, and single counts of larceny over $250 and unlawful possession of a large-capacity firearm.

“We reject the defendant’s claims, affirm his convictions, and, after review of the entire record … decline to exercise our power to grant extraordinary relief,” the court wrote in a unanimous 16-page decision authored by Justice Judith Cowin.

“From that terrible night in 2005 through all the post-conviction proceedings, this case was investigated and prosecuted with one goal: to ensure that a mass murderer was held accountable for the lives he took and the families he shattered,” Conley said. “We’re gratified that the high court affirmed the four murder convictions against Mr. Carnes and recognized the underlying fairness and integrity of his trial.”

On appeal, Carnes challenged the admissibility of two statements he gave to Boston Police homicide detectives during the investigation into the Dec. 13, 2005, quadruple homicide of Carnes’ friends in Duncan’s basement, which served as a makeshift music studio. In both statements, Carnes denied being at the scene of the murders. The SJC found that Carnes was not in custody when he gave his Dec. 22, 2005, statement and that he had voluntarily waived his right to remain silent when he gave his Feb. 10, 2006, statement.

Carnes further argued that the trial jury should not have received an instruction on joint venture for the firearms offenses, though his attorney did not object to the instruction when it was given. Prior to trial, Carnes’ co-defendant, ROBERT TURNER (D.O.B. 12/6/86) pleaded guilty to all indicted charges, including being an accessory to the murders after the fact and unlawful possession of the stolen firearms.

“Because the evidence supported a reasonable inference that Turner participated in the robberies … the evidence warranted a joint venture instruction,” the court wrote.

Carnes also argued that a special instruction should have been given after jurors sent multiple deadlock notes to the judge.

The high court found that the replacement of multiple seated jurors with alternate jurors reconstituted the deliberating jury each time, and that none of those reconstituted juries had deliberated long enough to warrant a Tuey-Rodriguez instruction, which urges deadlocked jurors to work toward a unanimous decision if possible.

“The short answer to this contention is that there was never a jury whose deliberations had been ‘due and thorough’ thereby requiring the Tuey-Rodriguez instruction,” the court wrote.

Carnes also argued that a juror who lied repeatedly on her jury questionnaire should not have been removed. The juror’s false statements were discovered after a victim-witness advocate assigned to the DA’s office recognized her as a past victim of domestic violence and notified the trial prosecutor of her observations.

“The judge found that the Commonwealth learned in a ‘benign’ manner that the juror may have made material misrepresentations on her questionnaire and that the prosecutor’s conduct was not improper. These findings are supported by the record. The Commonwealth’s course of action was a reasonable way of confirming the accuracy of the victim witness advocate’s perception and memory and it was not contrary to anything we said … prior to the trial in the instant case,” the court wrote.

Assistant District Attorney David McGowan of Conley’s Appeals Division argued the case before the SJC. First Assistant District Attorney Josh Wall prosecuted the case at trial. Kara Hayes, chief of the DA’s Victim Witness Assistance Program, was the assigned victim-witness advocate. Attorney Ellen Zucker represented the defendant on appeal.