People who aren't doing anything wrong should not be penalised, there's the presumption of innocence which is an underlying principal of a free state. Should police have keys to every house in case of domestic violence?
Nah battering rams are fine and more fun. It's also a good excuse for them to toss a flash-bang in the crib on the way in.
If somehow an un-pickable lock were the only way to get into a house and a sizeable portion of houses could practically be built that way, you can bet the courts would invent a reason why the government has to have the key in basically every anglo-sphere country. It would only take a few news stories about "women beaten to death while police desperately and futilely attempt entry" or "terrorist hiding in London house, alive and well years after attack but unable to be arrested" before half the public would start begging for something to be done about it.
That's not a analogous scenario though, because a) afaik police still need a warrant for a battering ram, they can't just enter, and b) battering rams are kind of a 1 time thing and very very obvious. The key is more like the police can just let themselves in at any time to check that there's no dv going on. If you're not home you don't even know if they were there. And incidentally some silverware has gone missing... That's closer to the scenario we're talking about.
Actually I'm in UK although it might be the same here. Second point still stands though: you can't tell if someone has been into your house.
Edit: to elaborate on "the silverware", "the police" having access means effectively anyone has access. It's not just 1 infallible person, you're giving that key to the whole station, and it's being kept somewhere, which makes it (more) vulnerable to theft, especially since a large cache of such keys is going to be much more attractive to a criminal than a single key.
