ABC TV's crime investigation by Debi Marshall of The Family Court Murders is a chilling revelation

THE FAMILY COURT MURDERS: Premiere Tuesday, 8.30pm (AEST), ABC TV and ABC iview

Investigative journalist Debi Marshall

Investigative journalist Debi Marshall

After 30 years, an unsolved domestic terrorism crime spree that shocked the nation finally saw the perpetrator found guilty on all but one of the 32 counts with which he was charged, thanks in no small part to the investigative prowess of crime journalist Debi Marshall.

In ABC TV's The Family Court Murders, Walkley award-winning Marshall reveals details of the four murders, five bombings, and two cold-blooded shootings in the 1980s.

Marshall says she was "gobsmacked" no one had been charged for the crimes when she began to look into them in 2012.

She says the prime suspect at the time - Leonard Warwick - was "living on the outskirts of Sydney free as a bird", but the police suffered from a lack of resources.

"When they brought him [Warwick] in, he invoked his right to silence," she said.

"The police didn't have DNA in those days. They put him under surveillance, but they had to pull it off, because they didn't have the resources."

In 1975, the newly established Family Law Court introduced no-fault divorce, allowing for wives to live apart from their husband for just 12 months instead of the previous period of five years.

In 1979, after years of abuse, Andrea Blanchard ran away from her husband Leonard Warwick, with daughter Trudi, and went to live with her father and brother Stephen.

The brutal attacks between 1980 and 1985 were fueled by the bitter custody dispute that ensued between Warwick and Andrea, and led to Warwick's revenge against those he saw as conspirators against him.

The compelling four-part series features exclusive interviews with the victims and their families - stories Marshall believes needed to be told.