Police are not able to sit around the table and decide for themselves who they will charge with murder,... it really does require a lot of hard, actionable, verifiable , reliable, evidence.. It requires any theoretical chain capable of being repeated in court , backed by evidence.
And then all this stuff goes off to the Office of the Public Prosecutor, where the Dept. of Public Prosecution hangs out, these are the people who take the Police case to court. So the police investigation team have to convince the OPP and the DPP that what they have is absolutely gold, and platinum, with diamonds thrown in. It has to be the kind of evidence that judge sees clearly for adjudication. By it's nature, it has to be more than someone just saying it happened, a lot more than that. That, on it's own, would not be enough.
Then, and only then, does a judge sign off on the warrant for arrest on the charge of murder.,
It has to be the kind of evidence that a jury sees, and hears and goes , 'yes. .. that was what was done, and he did it. ' .... no one in court has to worry about why he did it, that's for another day, another venue.
Once the OPP and the DPP are satisfied that the police have enough evidence to arrest someone, a warrant is issued, and off they go, banging on doors at 6am, because disturbance is the key , here. They want their arrestee disturbed.
VICPOL are not only convinced that Mrs Murphy is dead, but that she died early that Sunday morning, at Mt Clear, at the hand of Mr. S. These four things, not just him being charged with murder, but the claim of her death, and the location, and the timing points to VICPOL having some colossal , gigantic gold/platinum/diamond/ evidence, of the sort rarely falling into police hands....