I'm not sure why there's a fourth amendment issue here. The cops did not conduct searches to find evidence to ARREST THE HOMEOWNERS. There's never been a question the cops cannot order us from our homes if there's a dangerous situation, like a gas leak or impending flood, that requires them to act to protect the general public.
There just was not any seach and seizure.
It is a 4th Amendment issue because the 4th Amendment applies to all searches, not just criminal cases. Or do you think the government should be able to search your house at will?
So if government can search in hot pursuit of a a terrorist who's blowing up bombs in crowds and murdering people then they can search your house "at will." Got it...
Thomas Jefferson: "strict observance of the written law is doubtless one of the high duties of a good citizen, but it is not the highest. The laws of necessity, of self-preservation, of saving our country when in danger, are of higher obligation. To lose our country by a scrupulous adherence to the written law, would be to lose the law itself, with life, liberty, property and all those who are enjoying them with us; thus absurdly sacrificing the ends to the means."