Once upon a time, not that long ago, it mattered little whether police had a warrant to search your home or not. If they found something, it could be used against you.

Then along came a Cleveland woman named Dollie Mapp who took her conviction based on a warrantless search to the U.S. Supreme Court, and, 51 years ago today, won.

Dollie Mapp was a one-time girlfriend of two different prize fighters who rented rooms in her Cleveland home to fighters and other men looking for a place to stay.

YOUR CONSTITUTIONAL RIGHTS -- MAPP V. OHIO -- the case that spawned the "exclusionary rule" regarding illegally obtained evidence (1-minute podcast) 

When Don King (yes, that Don King) became the victim of a bombing outside his home in 1957, police thought the suspect might be at Dollie Mapp's house, so they went there to find out. But Mapp wasn't about to let them in without a warrant. So began a three-hour standoff. Police said they had a warrant but refused to produce it. They eventually broke down Mapp's door and stormed her home. At that point, they were so mad they decided they were going to find something -- anything -- to use against Mapp whether it was related to the bombing or not.

They turned her place over, finding some gambling receipts and a few "risque" publications including some nude sketches and bawdy stories. Police decided those materials violated Ohio's obscenity laws and arrested Mapp on gambling and obscenity charges. She was found not guilty on the gambling charges, but convicted of the morals charges and sentenced to seven years in prison.

The judge in the case said it didn't matter whether police had a warrant to look for the books -- the ends justified the means. An appeals court and the Ohio Supreme Court said the same thing.

But Mapp and her attorney, Alexander Kearns, pressed on, saying using the evidence found in an illegal search violated her Fourth Amendment rights. The ACLU filed a brief supporting Mapp and her case went before the U.S. Supreme Court.

In 1961, that court ruled that evidence obtained in violation of the Constitution, whether the case is in federal or state court, is inadmissible in court. Mapp had won.

And so did we.

Learn more about your rights when it comes to search and seizure.