"This case has never been officially closed," said McDonald.
"I'm hopeful that there will be closure and justice," he said. "Closure for all those who knew and really understand what was going on at the time."
The Albany County District Attorney's office had no comment when reached by ABCNews.com.
In the 32 years since the fire shocked the small town of Cohoes, the plot where the home once stood has been left vacant.
According to Greenberg, a couple had once expressed interest in buying the lot. But when they found out that that was where the devastating fire had occurred, they withdrew their offer.
Daniel Dwyer, Greenberg's chief assistant, made a point of visiting the Gratto family grave on the anniversary of the blaze every year until his own death in 1992.
Dwyer really spent the rest of his life trying to solve the case," said Greenberg. "He had on his desk a nameplate that said, 'Remember the Grattos.'"