A lawyer who acted for Arthur Allan Thomas says the review into the 1970 murders of Jeanette and Harvey Crewe demands a high-level judicial investigation, overseen by an independent body.
Police have announced they will review the homicide file on the case after questions were raised by the couple's daughter, Rochelle Crewe, but will not reinvestigate the killings.
Arthur Allan Thomas was convicted twice of murder and then later pardoned. No-one else has been tried.
Peter Williams QC, who appeared for Arthur Allan Thomas at the Royal Commission, says he is very disappointed the case will not be reopened.
He says police have never looked for the real murderer and the Thomas case has become a symbol of police malpractice.
Mr Williams says questions remain unanswered, and the inquiry could be overseen by a distinguished and independent overseas judge.
Rochelle Crewe, who was 18 months old at the time of the deaths, wrote to Police Commissioner Howard Broad asking him to reopen the case.
Arthur Allan Thomas told Morning Report he doubts the latest review will provide any fresh insight.