"Okay."

N.Y. search warrant case shows why we need the Exclusionary Rule: 

"The cop who filled out the search warrant didn’t specify which unit in a multi-family housing unit was to be searched. Consequently, the cops raided the wrong residence, which caused them to kick down the door and terrorize an innocent family. Someone could have been killed. It’s happened before. Hell, it’s happened before in New York...

The requirement that the location on a search warrant be specific isn’t “a technicality.” It’s a core principle of the Fourth Amendment. The entire reason we have a Fourth Amendment goes back to the general warrants the British crown issued to English soldiers in the streets of Boston in the 18th century. Those warrants, called writs of assistance, allowed British troops and inspectors to raid private residences in search of untaxed goods and illegal imports. The warrants permitted searches of any residence. These violations of private homes that required no probable cause stirred anger and resentment, and helped turn Boston into a hub of revolutionary fervor. So when a police officer today gets a warrant for a multi-residence building but doesn’t specify which unit is to be searched, and the police then raid multiple units within that building, they haven’t made a minor technical error — they’ve violated one of the founding principles of this country. This is isn’t an exaggeration...

It’s nearly impossible to sue a police officer in a case like this one. The number of times a cop has been criminally charged for an illegal search is barely north of never. Internal discipline for these kinds of mistakes is nearly nonexistent. (Want to wager on whether these cops were sanctioned in any way?) The Exclusionary Rule is the only real deterrent available. It not only discourages police from conducting intentionally illegal searches, it encourages them to use care and precaution to avoid mistakes. After all, if you’re subjected to an illegal search, it doesn’t matter if the search occurred due to malice or to negligence. Your rights have been violated either way. "