The family was infamously slain in Cheshire, Conn.
Joshua Komisarjevsky
As the sole survivor in the home invasion, Dr. Petit had been anxiously awaiting the decision in a conference room at the New Haven court with other family members.
"It's not easy," he said before the verdict was announced.
"We have a lot of family here. We have a lot of support."
Komisarjevsky's accomplice, Steven Hayes, was given the death penalty last December and remains in prison awaiting execution by lethal injection in Connecticut.
The jury deliberated for five days before voting Friday to send Komisarjevsky to death row, condemning him to the same fate as his accomplice in the 2007 crime.
The verdict ends two trials that showed jurors grim evidence - charred beds, rope used to tie up the family and autopsy photos taken after the Petit family murders.