Failings on the part of the police and probation service may have contributed to the killing of a woman by two convicted murderers, a coroner has concluded.

The body of Quyen Ngoc Nguyen, 28, was found in a burning car on Shiney Row near Sunderland in August 2017.

Her killers, Stephen Unwin and William McFall, were out of prison on licence having previously committed separate murders. They were convicted last year of Ngoc Nguyen’s murder and were given whole-life jail sentences.

During the four-day inquest into her death, the Sunderland coroner Derek Winter heard how failings by the probation service and police to share information with each other about breaches of licence conditions may have prevented the effective monitoring of the men.

Winter ruled that the death was an unlawful killing. “The perpetrators of her murder were subject to life licence conditions, the known breaches of which were not acted upon in a sufficient, timely and coordinated manner, including a failure of information sharing, all of which were not causative but possibly contributed to her death,” he said.

The inquest heard that Northumbria police recorded 26 “items of intelligence” on Unwin, of Houghton-le-Spring, between his release from jail on 20 December 2012 and Ngoc Nguyen’s murder more than four years later.

Among these was an incident on 2 July 2017 when a caller said Unwin had sent her a Facebook audio message threatening to “smash her jaw in” and to take turns with another man to rape her.

The court heard that information on this incident was not passed to the probation service, and the woman who reported it did not take the complaint any further.

Witnesses said Northumbria police introduced a new measure in April 2015 whereby “flags” – meaning items of intelligence – that appeared on the record of prisoners released on life licence would not automatically be passed to probation officials.

The change, designed to reduce workload, meant investigating officers had to pass on the intelligence themselves.

The court heard that Unwin’s police record incorrectly said flags would be passed to probation officials through Northumbria police’s multi-agency public protection arrangements (Mappa), despite the change.

The coroner said: “On the evidence, there were multiple occasions when information about Unwin could and should have been shared between the police and probation.”

Winter also said there was sufficient evidence to suggest Unwin’s accounts to his probation officer on the items of intelligence did not match the reality, and said they were not challenged effectively.

He said: “Life licence is based on trust and, having heard evidence, it is clear to me that both Unwin and McFall broke that trust consistently and were emboldened in all of their unlawful activities by what they must have perceived as the failures on the part of the authorities to expose their deceit.

“Evidence heard during the hearing demonstrates that there was a disconnect between the reality on the ground and, in particular, Unwin’s accounts to his probation officer. Although inevitably he would minimise his actions, there was little or no evidence that he was challenged effectively.” ﻿