Note: Not at the old Poker1 site. A version of this entry was originally published (2007) in Bluff magazine.

In some poker circles, I’m best known for my work with the body language of poker, usually known as tells. Mike Caro’s Book of Tells will celebrate its silver anniversary in 2009. That’s twenty-five years! Parade permits for London, New York, Boston, Los Angeles, and Tulsa are nearing the final stages of being processed, pending receipt of applications.

I kind of got pigeonholed when that book was published. I became better known for tells than anything else. And that annoys me, because, actually, most of my research has dealt with statistics and strategy, often backed by my own computer analysis. To put it simply, I’m a cross between a nerd and a geek who has been misconstrued to be a people-observing, prescient, kind-hearted guru. Oh, how that hurts!

Universal tendencies

Don’t misread me — I’m proud of my book, and those tells have stood the test of time. You don’t hear many people arguing with words like “Caro was wrong. A player isn’t holding a strong hand when he does that; he’s bluffing.” And there’s a reason you don’t hear such quibbling. All those tells came from deep within me and deep within other players. When you learn about these tells, you instantly realize that, hey, they really are universal tendencies — players really do act that way to disguise their hands, because you tend to do that yourself!

Today, I’m going to talk about bluffing. Specifically, I’m going to talk about how to know when an opponent is bluffing through use of tells. Here are some major things you need to know:

Keys to bluffing

Bluffers are afraid to trigger your calling reflex. I’ve previously shared the secrets surrounding the “calling reflex.” The concept is that nobody comes to a poker room hoping to throw away hands. Instead, players gather at the table hoping to play hands and make calls. This bias toward calling, rather than folding, means that players are more suspicious than they should be. Any erratic movement or speech coming from the bettor is apt to trigger their calling reflex or, at least, to make a call more likely. Now, here’s the deal. You and I understand that intellectually. But others understand it unconsciously. Years of poker warfare have made them vaguely aware that their actions can cause suspicion in opponents. That’s why most bluffers refrain from taking actions that might cause suspicion and trigger calls. In fact, sometimes bluffers barely breathe. On rare occasions, they don’t breathe at all. I carefully observe opponents breathing when they bet. Often bluffers tend to take unusually shallow breaths. They’re afraid that loud breathing will lead to suspicion and a resulting call. So they over compensate. Watch carefully to see how an opponent breaths under normal circumstances. If that player’s breathing is significantly less pronounced following a bet, there’s a good chance you’re up against a weak hand or a bluff. This advice is especially valuable on final-round bets in limit games and anytime a large wager is made in no-limit games. Bluffers are unusually still. You should always note how animated an opponent is after betting. There is often an obvious decrease in movement if an opponent is bluffing. Players who have wagered on strong hands are typically more relaxed and their movements appear natural. Bluffers are more rigid and restrained. Often they freeze. They try to appear invisible, fearing that the slightest motion will trigger your call. Think of a person hiking through the mountains and encountering a rattle snake. If they’re smart, they’ll freeze, wanting to do nothing that will encourage a strike. That’s how bluffers act. If bluffers move at all, it’s usually at the last moment in desperation when a call seems almost inevitable. But, even at that final, fateful moment, most tend to remain still. Bluffers can’t carry on sensible conversations. If you’re not certain if your opponent is bluffing, try to initiate a chat. Those with significant hands are able to talk normally, and what they say makes sense. Bluffers will often sound stilted, instead. Their words — if they talk at all — will seem unfocused and unnatural. Bluffers may look back at their cards when you begin to call. If you’re still not sure whether your opponent is bluffing, fake a call. Reach menacingly toward your chips. As a sign of panic, bluffers may look back at their cards, trying to convince you that they hold something monumental. This is a dead giveaway. Players who really do hold strong hands won’t take any action at that key instant to stop you from completing the desired call. They’ll simply stay still and let it happen. Bluffers don’t show any change in mood whether you appear to be calling or raising. Here’s an advanced ploy I sometimes use to elicit clues about whether an opponent is bluffing. First, I’ll count out enough chips to call. Then, after a dramatic pause, I’ll add to the call amount, suggesting I’m planning to raise, instead. Players who hold strong hands often will react differently. A call and a raise are dissimilar to a player betting from legitimate strength. A call may be desired and a raise worrisome. So, if I see a change in reaction, it’s more likely that the bettor has genuine strength. But bluffers don’t care. A raise and a call spell the same doom, so their reaction is unlikely to change. If I see no modification in response, I give more credence to the conclusion that the opponent is bluffing.

Anyway, I hope that helps. Gotta go, phone’s ringing. — MC