The alleged murder of eight-year-old Bradyn Dillon by his father Graham Dillon, 37, last week reignited debate about family violence and issues of child protection in the ACT.

Many of those who knew the young boy have taken to social media, calling for more to be done to prevent family violence.

Their cries echo those made after a spate of four family violence-related deaths last year.

Police data provided to Fairfax Media paints a disturbing picture of the proportion of recent killings associated with family violence.

Twelve killings have occurred in the ACT since 2012 – a number that, like most crime types in Canberra, remains low compared to the rest of the nation.

Of the 12, eight have been family violence-related, and six of the victims have been female.

Tara Costigan Foundation chief executive officer Michael Costigan said the figures, while not surprising, helped illustrate just how "massive" the problem is.

"My guess is that if two-thirds of all murders are the result of family violence, then I'd probably extrapolate that two-thirds of any violence, whether it causes a fatality or not, is the result of family violence," he said.

"This is a major, major endemic problem."

Mr Costigan lost his niece, Tara Costigan, last year to a shocking alleged act of family violence.

Ms Costigan's former partner Marcus Rappel, 40, is accused of killing her with an axe in Canberra's south a day after he was served with an interim domestic violence order she had taken out against him.

Her death was one of five alleged murders last year, four of which were family violence-related. That is a significant spike on the 10-year average of 2.3 homicides per year.

Nationally, the number of homicides have been on long-term downward trend, according to the Australian Institute of Criminology.

Mr Costigan said that homicide statistics failed to reflect the "ripple effect" that such acts caused on family, friends and the community.

"When you take Tara for example... there are three children who don't have a mother," he said.

"You think of all of our family, all of the friends. My five-year-old daughter is a victim of Tara's murder.

"The ripple effect of all this is massive and I don't think we really understand it."

Domestic Violence Prevention Council chair Marcia Williams said recent deaths had challenged many people's understanding that domestic and family violence only related to abuse from an intimate partner.

"Often people forget that it can be other family members. It's about coercion and control and people exerting power over family members and that can mean children, and often parents and elderly parents."

The ACT government in 2014 ordered an inquiry into domestic and family violence deaths and the council is set to release its findings in coming months.

That review will look specifically at closed investigations and will not cover more recent family violence-related deaths that are still before the courts.

"We've been relatively sheltered compared to other states in terms of the number of deaths, but in the past two or three years a lot of those incidents have led to death and it's a reminder to people of what to look out for," Ms Williams said.

"[Domestic and family violence] is not a one-off incident."

Experts cannot say exactly how many deaths have been linked to domestic violence in the territory, with some resulting from homicides and other causes.

The ACT Domestic Violence Crisis Service estimates there were 72 deaths between 1988 and April 2012.

The review's findings are expected to lead to reforms aimed at reducing the number of deaths, including through sharing information by courts, law enforcement and social service agencies.