The Police and Lying

First and foremost, the police are 100% able to smell a lie right away. Your body is almost always going to give you up if you're lying. The police can always tell when a suspect is lying, from body language to nervous tics and more. Even if you think you're telling the truth, the police can still detect a lie

Bloodshot eyes

-This can be an indicator of suspicious activity. This can tell police if you're up to something. And if they ask, and you have allergies, tell them that. Otherwise, they will think something else is up. And plus, if you have bloodshot eyes and reek like you slept in a bar, that tells them a nice little present known as a DUI/OVI/DWI will be coming to you

Uncontrollable/Strange Laughter

-Some people laugh or crack jokes when nervous. If you're the one who is the complete comedian but seizes up like a deer in the headlights when officers are around, work on that. That's a huge tell to police. According to a veteran officer "Generally, if someone is giggling like a school kid and surrounded by others, they are typically just nervous but aren't worried about your presence. It's when you see someone joking around and they suddenly freeze up when they notice you, those would be the people I'm interested in."

Excessive Sweating

-First and foremost, this is an absolute dead giveaway that what you're saying is not the truth. When you are doing the Polygraph Test, aka "lie detector test", that is why you have the sticky things on your finger. When you lie, that detector can sense it and thus, will reveal it to the person conducting the test. It is revealed through electric-type receptors in the body, which can cause sweating. The same officer reveals "how sweat is a good indicator of truly suspicious behavior. You would be surprised how much people sweat when they are trying to hide something."

Avoiding Eye Contact

-A lot of people will often make direct eye contact with people to show respect, to show they have your full attention, to show they are interested in what you have to say, to tell the truth and more. Direct eye contact can say a lot. If you want to lie successfully, look the person in the eyes. According to one deputy sheriff "When you talk to someone you usually look at them right? Even if you're just nervous you still look at the person talking to you or the floor. The people who I get a 'gut feeling' about are always looking at anything but me. It's a weird kind of subconscious mental process where the person's eyes are always looking for a way to escape." And if your eyes are moving around constantly, you're either lying or on some sort of narcotic that causes nervous behavior, body twitching and more

Giving Up Information That Can Backfire on You

-The more you lie, the more crap that builds up only to roll back downhill on you. The more you lie, the worse it will look. According to one deputy sheriff "Usually when someone has something to hide, they will continually add unimportant information to their fraudulent story. If it doesn't make sense with the surrounding situation, no amount of additional information makes it more believable."

Giving Off "Weird Vibes"

-Secondly, after the "excessive sweating" being the first and foremost indicator of lying, there is the second most important indicator of lying. When you're giving off a "weird" or "suspicious" vibe, the police will pick that up right away. According to one officer "At the end of the day people who are nervous because they got caught act differently than people who are just nervous. The body language is different. They just give off a different vibe."

Moving Your Hands Around/Shoving Them in Pockets

-This is a red flag that you have something you shouldn't or you're trying to hide something. In cases like this, it's usually narcotics trying to be hidden. Police notice suspicious behavior and moving your hands around is like saying, without words "I'm trying to hide something" or "I'm suspicious". One officer noted "Suspicious people focus on how [they're] guilty. If they're holding, they keep putting their hands in their pocket. If they've got a concealed gun, they'll keep touching the clothing over it. If they're driving and they've had too much to drink, they'll put their hands over their mouth to smell their own breath."

Saying "I Swear to God"

-It's been stated as a fact that no one has sworn to the truth and used God to do it. It's also been said that it's the same for swearing on your mother's grave. From the words of one officer "In my experience as a cop every single time someone emphatically says 'I swear to God', I know they're lying to me."

Looking Over Your Shoulder

-One officer commented on Reddit that there was a guy on his force who had an unorthodox, but highly successful, foolproof method of catching criminals. "[The cop] would stand on the corner of a busy downtown street and stare at random passersby. If one of them turned around and looked back before he got out of sight, he would arrest him. In almost every case the guy was wanted for something." While this doesn't seem like the most reliable way of catching criminals, it gives you a taste of what police psychology is like. And whatever works, go with that

Strange Mannerisms

-Like the old cliche goes, "act normal". If you're acting strangely or suspiciously, naturally the police are going to turn their attention to you because they think you have something to hide. Eye contact not with the police officer's eyes, suspicious behavior, odd mannerisms, strange appearances all scream "I'm suspicious" unless you just have strange mannerisms anyway

Saying "You're just going to a friend's house"

-This is a stock excuse uttered by thousands of criminals, usually in murder or drug cases. Don't use this; the police will automatically know something is up

Literally taking off running

-Obviously, any person knows that immediately fleeing from police will result in a chase. And if the police lose the suspect, they then flood the area with officers, call in police dogs and will even use helicopters with heat sensors on them to pick up the body heat of suspects in hiding. There is no hiding from the police. If you immediately take off running, you're guilty! In the words of one officer "I consider running from police one of the stupidest risks you can take with your life and well being. I'm not going to lie, if I have a legitimate offence and a suspect, and that suspect runs away, I enjoy chasing them down and arresting them. But if the police dog gets involved, it gets really ugly. Why risk your life and limb for something minor? I personally think it's better to chance it out or walk away casually than run from the police."

If what you are currently doing is not connecting with the time of day

-The time of day indicates a lot of things. Police are highly aware of what they consider "normal" behavior for all times of the day. Most police often work the same shifts and they notice what is "normal". Around 5:00 pm, they'll see people in work clothes heading homes from offices or to the bar. If something seems off for that particular time of day, they'll take notice. One person at Reddit noted "It also largely depends on what shift you work, who you usually deal with and what kind of calls you typically take. We survey the whole situation. What time of day is it? What is your story? How many of you are there? What kind of place are you in?"

Immediate Non-Cooperation

-Cooperate with the police. Simple as that. It goes better. It's been noted that it's often worse for the suspect if they don't cooperate. In the words of one officer "One thing that stuck out to me is that the innocent folks were usually both cooperative and upset at the same time. I'd give them the cliche talk of 'everything will be fine if you've done nothing wrong,' and 99% of the time the innocent people were cooperative but vocally upset at being accused or investigated for a crime."

Having anything on you that could be used in criminal activity

-This might sound odd, but police are trained to look for anything suspicious. If you have drug paraphernalia on you, also known as drug-related items like syringes, bongs, etc., that tells the police you plan on doing drugs. If you have an open container, you're drinking and driving, etc. If you're out and about wearing dark clothes and carrying a strange bag in the middle of the night, and an officer sees you, the first thought popping into their head is breaking and entering. Context is key. Context is what helps officers do their jobs effectively. They look for what is out of place with the location and time of day. One officer noted "We look at the whole picture. What is the context of our interaction? Am I responding to a report of a crime, do you match a suspect description? [...] If I stop a suspected burglar with a backpack and he has a history of burglary and no reason to be in the area, his nervousness is more likely because I caught him red handed."