Legal Question in Constitutional Law in Nevada

No it is not an absolute bar.

While the fourth amendment requires a warrant for search, our crooked cops and the courts have carved out many exceptions.

In fact, there is very little left to the 4th amendment. Cops will simply lie and say you consented to a search, or they will falsify documents and testimony to show some reason for an exception to the warrant requirement. These days cops invade homes of the innocent and claim they do it by right.

Mr. Otto's answer is far too cynical.

The Fourth Amendment only bars unreasonable or warrantless searches. Police are allowed to conduct searches with warrants, with the consent of the searched party, or in a variety of circumstances where a warrantless search has been deemed reasonable.

As Mr. Otto notes, police officers sometimes lie in order to justify illegal searches. That does not mean the Fourth Amendment allows them. Just as murder is illegal even though people sometimes get away with it, so are unreasonable, warrantless searches.