10 Strange Historical Interrogation Methods and 10 That Actually Worked

In the Middle Ages, English courts used a method called “corsned” or “judgment by consecrated bread” to determine who was lying. Specifically, the suspect was forced to swallow a large piece of dry bread and cheese while a priest recited prayers asking God to make him choke on the food if he were guilty. Since a dry mouth is a natural reaction to intense stress, a guilty person could actually pass the test by swallowing this repulsive snack.

Similar to the technique described above, some cultures required suspects to place their tongues on a piece of metal heated to red-hot. If you were telling the truth, your mouth would produce enough saliva to prevent any burns, but if you were lying, your mouth would be as dry as a desert because of your nervousness. As you can imagine, this method didn’t work very well for most people.

In a sort of reverse psychology ploy, the interrogators would bring a donkey into a dark tent and tell the suspects that they had to go inside and grab its tail. The authorities would first coat the donkey’s tail with soot, then tell onlookers that the donkey would bray only when the guilty party grabbed its tail. When the suspects emerged from the tent, those whose hands were not covered in soot were arrested for being “too afraid” to grab the donkey.

Do you need to prove that you’re telling the truth? Easy! Just walk across nine red-hot plowshares. Anglo-Saxon law sometimes used this technique to test innocence, and if you managed to recover within three days without getting an infection, you were free to go. It seems you either need some serious calluses or you’re just lucky with this test.

In ancient India, if a suspect was suspected of lying, he was weighed on a scale against a designated weight. Officials would then read a list of charges to the suspect before weighing him again. If they were heavier the second time, they were declared innocent, but if they were lighter… you guessed it, they were declared a liar. From a scientific standpoint, this doesn’t make much sense, but at least it kept everyone on their toes during the trial. It’s just strange to think that the gravity of a lie could actually change your mass.

In ancient China, investigators would make suspects chew a mouthful of dry rice and then ask them to spit it out. If the rice was still dry, they were deemed guilty, because fear had caused their salivary glands to stop working. Fun fact: this ancient technique is actually based on a scientific principle. Admittedly, it’s not very scientific or very classy to force someone to spit rice all over the floor during an investigation, but that’s how it was. I hope you weren’t thirsty that day.

The cross test was essentially a battle of will and strength. Each party—the accuser and the accused—would stretch out their arms to form a cross with their bodies. The one whose arms gave out first was considered the liar, because God strengthened the body of the person who was telling the truth. Seriously, guys, the next time you work out, skip the shrugging and head straight to court. I promise you’ll improve your posture that way.

Suspects were sometimes asked to prove their innocence by retrieving a ring from boiling water to show that they weren’t hiding anything up their sleeves. Apparently, if your hands weren’t burned a few days later, you were considered honest in the eyes of the law. It’s hard to imagine that anyone could emerge unscathed from such a situation, no matter what they had done. It seems like a great way to test the power of “God’s will.”

The “test” everyone knows about for a wide range of crimes: if you floated, you were guilty, because the holy water rejected your sinful soul. But if you sank, you were innocent! Of course, drowning was probably a better alternative than being found guilty, so you’d better hope someone would help you out of that pond quickly.

Now that we’ve covered 10 strange methods, here are 10 from history that still work today.

Listen, we’ve all seen this technique before, because it’s been used in every cop interrogation scene known to humanity. But it works. The fact that one interrogator is hostile while the other calmly steps in as a “friend” who’s only trying to protect you creates a dynamic that psychologists call… something. Basically, you end up hating one person and starting to trust the other, which makes you want to cooperate with them by revealing your darkest secrets to avoid the harshness of the “bad cop.”

These days, police officers ask you about your day or your favorite movies before getting to the heart of the matter. Why? To determine how you behave when you’re telling the truth, so they can identify the signs that give away your lies. Maybe you start moving your knee or speaking faster… they’ll notice. Once they’ve established a baseline for how you lie, they’ll only ask you questions that require short answers. Everything you say after that can be analyzed to catch you in the act of lying.

Rather than presenting all their evidence at once and immediately proving that you are a liar, some interrogators wait for you to say something false so they can confront you with evidence that refutes that specific statement. By repeating this process several times, the suspect gets the impression that the police officer knows everything, which often causes them to crack and confess to their crimes. Once a suspect believes their story has been debunked, they confess to their crime almost impulsively.

Most people have heard of this technique, whether it’s called the “Reid technique” or the “good cop/bad cop routine.” One of the most effective ways to elicit a confession is to follow a 9-step process that psychologically pushes you until you give in to the pressure. In step 5, the good cop begins to present false “themes.” Themes are pre-packaged excuses for the crime that your investigator presents to you as if they were your own thoughts.

Who’s better at lying than a liar? Liars. One of the easiest ways to expose a liar is to let them talk. Tell your interrogator everything. The longer they listen to you talk, the more likely you are to make a mistake and say something that incriminates you or your partner. If you manage to get your interrogator to ask you at least five questions, you’re probably guilty.

Well, you probably shouldn’t become friends with the suspect, but some of the best investigators make suspects feel that they, too, are human beings. By putting a suspect at ease, you’re more likely to get them to let their guard down and reveal information. Most criminals won’t turn in their accomplices if they feel that the person questioning them respects them as human beings. If the person questioning you offers you a cup of coffee and speaks to you politely, you’ll be more inclined to respond in kind.

Hanns Scharff was a German interrogator during World War II who extracted information from thousands of prisoners of war without ever raising his voice. He would take the prisoners for walks, share his homemade cookies with them, and talk about everything except the war. One pilot even stated that he “was allowed to go to Scharff’s office whenever he wanted… to play his piano and talk about anything but the war.” This made Scharff a master at gathering high-level intelligence. The pilots would enter the German’s house all smiles before letting their guard down and making mistakes without even realizing it.

Memory and attention are two things your brain can only handle to a certain extent at a time. If you force a suspect to multitask while telling their “story,” they’ll likely have trouble keeping the details consistent if they’re making up the story. You can ask the suspect to recount their version of events in reverse order, to tell their story while doing puzzles, or simply ask them questions that are too complicated for them to answer without thinking. If they’re lying, they’ll have a hard time getting out of it.

This method is based on the principle that traditional interrogation techniques often lead to false confessions. By remaining impartial throughout the interrogation process, you ensure that you don’t miss any key clues. Follow the “PEACE” principle: an acronym that stands for Preparation, Engagement, Reporting, Closure, and Evaluation.

Ask any teacher. If you let too much silence linger during a conversation, people will just talk to fill the void. Most interviewers remain frustratingly silent after you’ve answered a question, hoping you’ll keep talking. Whether it’s to elaborate on your answer or simply to speak off the cuff, you’ll end up saying more than you intended if you’re not careful.