Suffolk District Attorney Ray Tierney told News 12 in an exclusive interview that his office is further examining ways to protect children now that the Thomas Valva murder trials have ended.

Both Thomas Valva's father, Michael Valva, and Angela Pollina were found guilty of murder in the 8-year-old's death.

"The guilt of the main actors, that has been established," Tierney said. "Now we move to the second part of learning from it and hopefully improving the system."

Tierney said there are many things that the district attorney's office can do, and he believes the most powerful tool they have is the grand jury. He did not confirm if they will seek a grand jury special report or not.

Thomas Valva was killed in January 2020. That March, former District Attorney Tim Sini called for a special grand jury to investigate the circumstances that led to the child's death.

Tierney would not confirm on whether a more comprehensive investigation into Child Protective Services has begun.

Staffers at East Moriches Elementary School testified that they filed several CPS reports about Thomas Valva.

"At the end of the investigation, you publish findings and facts, and then you have recommendation in the form of a grand jury report," Tierney says. "You can talk about this is what happened in this case, and this is some things we can implement."

Tierney says his office does not comment about ongoing investigations but went on to say, "there is nothing to say it hasn't already begun."

Stay with News 12 for the second part of the exclusive sit-down interview in which Tierney talks about the pieces of evidence he feels helped win the case.