The police can walk right through your door if they think that a crime is/has been committed. In the latest instance all they'd need is a warrant and a battering ram to enter and investigate for leads.
What no one seems to understand is, there's the Joe Bass' of the world (anytime/anywhere), and the rest. Was it necessary to send the last alert as far as Winnipeg (it's a yes or no answer)? Alerts to the Golden horseshoe for a custody squabble in Thunder Bay? Wait 5 1/2 hours till 2/3 of the province was in bed to send an alert? Unless they find a way to make the system more streamlined/location specific the Car Alarm in the City Phenomenon (aka urban crickets) will come into play. The alarms will be sent out and a whole hell of a lot of people will think "Not again. Probably some guy and his wife squabbling over custody in Moosonee" and ignore it, They'll turn their electronics off/silent, then go on with what they were doing.
If a crime has been committed(Past tense) they wait for a warrant. If they suspect a crime is being committed there is probable cause to enter without a warrant. I'm sure sometimes a cop thinks he hears someone scream.
There is a process for an Amber Alert and they don't hand them out like pizza coupons. The down side is the time it takes. The trade off is that the alerts are few and far between so people don't normally mute them.
It would be interesting to know how many drama queens asked for alerts when a custody issue is bitter and hubby / wife took a few extra minutes of kid time.
The time at risk started when the dad left the party with the girl, not when mom reported the situation. In a planned abduction a kidnapper can put a lot of miles on fast.
The father is being charged with first degree murder indicating planning and has been medically treated, indicating a possible suicide.