For those who are so wary of police doing a thorough investigation, consider the possibility that a couple of thugs are inside your house, holding you hostage, raping your wife. The police knock on the door and one of them answers the door and tells the officer that everything is okay and yes, he is the homeowner, and no, the officer may not come in. The officer accepts his assurances and goes back on patrol....
Or the also more common situation where husband is beating the wife, answers the door and tells the officer to go away.....
I know there are no perfect answers, but I believe there is a reasonable middle ground that both sides need to respect.
Ken