The man convicted of killing a Nassau police officer back in 1975 could soon be paroled, but the officer's family is fighting to keep him behind bars.

Nassau Police Officer Matthew Giglio was shot while responding to a burglary more than 40 years ago. He died a few weeks later. His son, Matthew Giglio, was just 4 years old at the time.

John MacKenzie was convicted of Giglio's murder and sentenced to 25 years to life in prison. He has so far served 40 years behind bars, but becomes eligible for parole every two years.

Matthew Giglio and his two sisters are now asking the state to once again deny MacKenzie parole.

"He has no respect for human life. We don't feel he deserves the chance at freedom," says the slain officer's son.

But MacKenzie's supporters have started a blog asking people to write letters asking for MacKenzie's release. It says MacKenzie has worked to help others behind bars and "would like to continue his work as an advocate for victims' rights if he is granted parole."

In a 2000 interview with News 12, MacKenzie said he is remorseful, but doesn't remember the shooting because of drug use. "After years of reading everything, I came to the realization that I did, and that was a hard pill to swallow," he said at the time.

Officer Gilgio worked in the 5th Precinct in Elmont. A plaza along Corona Avenue is now dedicated to his memory. Giglio's children say the best way for the state to continue to honor their father's memory is to keep MacKenzie in prison.

"It took MacKenzie seconds to pull the trigger that night, but it caused my family decades of pain and suffering," says the officer's daughter, Regina Giglio.

The parole hearing process began this month. The Giglios say it normally takes months for a decision to be reached, and they do not expect an answer until later this year.