The Herald reports:
An elite police criminal profiler built a psychological model of the murderer who killed the Crewes – and ruled out the motive detectives say drove Arthur Allan Thomas to commit the crime.
The profiler also diminished the role of Jeannette Crewe in any motive, saying a dispute between her husband Harvey and the killer likely festered for four years until the murder was committed through a “distorted desire to punish”. …
The profiler identified up to six criminal acts against the Crewes in the four years before their murders. They included a burglary in 1967, a fire in the Crewes’ nursery in 1968 and the destruction by fire of a hay barn in 1969 – the year before the double murder.
The pattern showed “escalating criminal progression”.
“Someone did not like them and their hatred was evolving over time. The burglary and fires were precursor offences by the perpetrator of the murders.”
The criminal profile said the killer knew the Crewes well and “wanted to intimidate” and “possibly drive them out of the district”.
If Ewen Macdonald was alive in 1970, I’d suggest they go interview him
I used to think it was Len Demler, but who knows.