A motion was filed Friday on behalf of Joshua Komisarjevsky, the New Haven Register reported. His legal team portrayed Steven Hayes, who was sentenced to death last year, as the most active in the crime, saying he killed Jacqueline Hawke-Petit and her daughters.
Allowing Komisarjevsky, 30, to plead out would spare the state a "lengthy, expensive and emotionally charged trial," the lawyers told Superior Court Judge Jon Blue.
Hayes, 47, depicted Komisarjevsky as the most responsible for the killings.
Jury selection is scheduled to begin Wednesday in Komisarjevsky's trial, although testimony is not to start until September.
William V. Dunlap, a criminal law expert at Quinnipiac University, told The New York Times the judge is unlikely to grant the motion.
"The court may well want to leave it to a jury to decide whether Hayes's and Komisarjevsky's culpability were similar enough that since Hayes was sentenced to die, Komisarjevsky should be, too," Dunlap said.
Dr. William Petit, who was beaten with a baseball bat during the invasion of his home in Cheshire in 2007, is expected to testify again.