Ms Wilkinson, a mother-of-three, was allegedly set alight by Johnston at her Arundel home on Tuesday.
Prof Petherick said issues of domestic violence, such as coercive control, needed to be addressed through early intervention.
He said if it was identified in a current relationship it needed to be treated as if there was an "inherently high risk".
Prof Petherick said there was evidence "for what needs to be done" and the lack of proactive action was akin to the "thoughts and prayers" that followed a mass shooting in the United States.
"We know coercive control is a problem. We know fixation and obsession are a problem with domestic violence. Yet we aren't really doing anything about it. It just seems like every time there is a death of a woman at the hands of an angry man we say 'thoughts and prayers' or 'hopes and prayers' without there being any real action.