Michael Stone, who murdered Lin and Megan Russell, was labelled dangerous and a threat to the public on numerous occasions in the months leading up to the killings.
A report published tomorrow is expected to highlight failings in both the healthcare and criminal justice systems that left Stone at liberty to carry out the brutal crimes.
The independent inquiry chaired by Robert Francis QC is also expected to say doctors failed to ensure that Stone was receiving his anti-psychotic medication.
Michael Stone was convicted in 1998 of battering Mrs Russell and her six-year-old daughter Megan to death with a claw hammer. It prompted Jack Straw, as Home Secretary, to pledge new measures to detain people before they commit a crime even if considered untreatable by psychiatrists.
Controversy over the Russell murders reignited yesterday after it was revealed that the case may have to be reviewed after criticism of the pathologist who examined the bodies of Stone's victims.
The Home Office confirmed that Dr Michael Heath had resigned from its official register of experts after having been censured at a disciplinary hearing. Government lawyers are deciding whether to review the hundreds of examinations he carried out over the past 15 years.
The findings of the investigation into the supervision and treatment of Stone have been suppressed until now because of legal challenges by Stone, who did not want his medical history made public.Reuse content