British Columbia's child watchdog wants dramatic changes to the way the province assesses and protects children at risk from violent family members.

Mary Ellen Turpel-Lafond's scathing assessment of how the province failed three Merritt, B.C. children who were killed by their mentally ill father in 2008 was released Thursday.

In it, Turpel-Lafond said the deaths of Kaitlynne Schoenborn, 10, and brothers Max, 8, and Cordon, 5, could have been prevented.

The report prompted an apology from B.C. Premier Christy Clark with a promise to bolster services for domestic abuse.

Turpel-Lafond told Canada AM that B.C. must act now. "It has to," she said.

"When we look at the experience of this family and these three children, we find out that the child protection system, justice, mental health system didn't work effectively despite many opportunities. And these children died.

"That's a very significant wake up call to our systems that we have to do better. We have to put in place effective leadership and co-ordination that domestic violence is taken seriously in British Columbia."

In her report, Turpel-Lafond said authorities were in contact with the Schoenborn family at least 14 times in the week before they died. The children's mother told police she was terrified of her husband.

This isn't the first time Turpel-Lafond has criticized B.C.'s social service agencies and the criminal justice system.

She wrote a similarly scathing assessment of how authorities responded to another troubled family. Peter Lee of Victoria fatally stabbed his wife, in-laws and six-year-old son in 2007.

Her report on the Lee murders prompted a government promise to reduce domestic violence, but some of those services were later cut.

Turpel-Lafond said she was disappointed to find nothing had changed. If anything B.C. lags behind other provinces.

"British Columbia, unlike Alberta, Ontario, Saskatchewan, many other provinces, doesn't have domestic violence courts," she said.

"There are things that we don't have here, that we have lost our focus on and we need to bring that back."

Allan Schoenborn was later found not criminally responsible for killing his children due to a mental disorder. He is now at a psychiatric hospital.