Wearing gloves at a crime scene seems like a no-brainer. Not only does it help prevent the contamination of evidence, it also keeps police and investigators from getting bodily fluids on themselves. But believe it or not, officials were going into grisly crime scenes bare-handed until 1924. The Emily Kaye case changed all of that.

The case kicked off when a British woman named Jessie Mahon found a suspicious left-luggage ticket in the pocket of her husband Patrick’s jacket. Knowing that he had been acting strangely recently, Jessie sent a friend, who happened to be a former railway policeman, to investigate. When the friend turned in the left-luggage ticket at Waterloo Station, he received a bag containing women’s undergarments and a bloody knife. Though he must have been shocked, he put the bag back, and told Jessie to return the ticket to her husband’s pocket. Meanwhile, he informed police, who kept the locker under surveillance. When Mahon came to get his bag on May 2, 1924, they nabbed him. After being taken to Scotland Yard, he eventually confessed to a horrific crime.

Mahon claimed that he and his mistress, Emily Kaye, had gotten into a fight. During the argument, she fell and hit her head on a coal bucket and died. Fearing that he would be charged for murder, Mahon went to elaborate lengths to dispose of her body.

Police would eventually discover that Mahon’s version of events was a lie. In the Sussex bungalow Mahon had shared with Kaye, there was no sign of the quarrel he had described. The coal bucket was flimsy and undamaged. Police also discovered that Mahon had purchased the murder weapon three days prior to meeting Kaye. Furthermore, Kaye had been pregnant.

What Mahon didn’t lie about was the extreme methods he took in an attempt to hide the evidence. After dismembering Kaye in the bungalow they’d shared, he’d stuffed much of her headless body into a large trunk marked “EBK.” He removed some organs and hid them around her bungalow in biscuit tins and hat boxes. He boiled other body parts in a pot.

Needless to say, the crime scene was utterly horrifying.

Sir Bernard Spilsbury, a famous British pathologist, was called in as the chief medical examiner on the case. Spilsbury asked officers to collect the remains for further examination. Officers rolled up their sleeves and started tossing body parts into buckets, “as if they were sorting fish on a quayside.” Shocked, Spilsbury asked them if no rubber gloves were available, and they responded that they never wore protective gear of any kind.

By the next big murder case, Spilsbury had created the “Murder Bag,” a kit for police officers to carry that included rubber gloves, a magnifying glass, a tape measure, a ruler, swabs, sample bags, forceps, scissors, a scalpel, and other instruments. Suiting up with gloves before entering an active crime scene has been standard procedure ever since. The glove method isn’t the only thing the Mahon/Kaye case inspired, by the way—Alfred Hitchcock used details from the sensational story when he was making Rear Window.

And just in case you thought a contaminated crime scene might have gotten Patrick Mahon off the hook: He was found guilty and executed five months after his arrest.