VEGAS MYTHS BUSTED: Gonzalo Garcia-Pelayo Invented the Only Technique to Beat Roulette Without Cheating

Posted on: January 27, 2025, 08:01h. 

Last updated on: January 27, 2025, 03:18h.

Corey Levitan Read More

Expertise: Commercial Gaming, Entertainment, Expert Insight, Las Vegas, Restaurants, Las Vegas Myths.

“The story of how the only profitable roulette system was uncovered and how the man that discovered it won $1.5 million, is a tale that continues to inspire casino fans new and old,” reads the Times of Malta’s April 21, 2022 edition.

If you know roulette, then you know the story of Gonzalo Garcia-Pelayo. The Spanish filmmaker used his system to win big. Then he got banned from casinos in Spain and all over the world. He wrote all about it in his 2003 book, “The Fabulous Story of the Pelayos,” that got turned into an episode of the History Channel’s 2005 series, “Breaking Vegas.”

The way Garcia-Pelayo tells it, though, no other gambler had thought of his idea before. And that’s self-mythology.

Wheel of Fortune

In the early 1990s, Garcia-Pelayo designed a computer program to exploit imperceptible imperfections in roulette wheels. He and his family members gathered data from the wheels at Casino Gran Madrid. Then, Garcia-Pelayo’s program analyzed it for patterns.

European wheels have 37 slots, numbered 0 to 36, that should give you a 1-in-37 chance of hitting any slot on any spin. But what Garcia-Pelayo found was that, on some wheels, certain numbers came up only every 30 or fewer spins.

These patterns are impossible to spot in real-time. But when crunched by Garcia-Pelayo’s program, the patterns in the tens of thousands of results tediously recorded by his family jumped out and screamed.

Armed with the knowledge of which wheels favored which numbers, Garcia-Pelayo and his family placed their bets and won 600K euros (around $625K) in a single day at Casino Gran Madrid, according to the Spanish newspaper El Pais, and — after that casino banned him in 1992 — over 1M euros (about $1.25M) during a similar spree around the world between 1991 and 1995 that hit Las Vegas’ MGM Grand.

Myth Interpreted

“I don’t have doubts that he won by finding biased wheels, but the implication that he invented the method is unfactual,” Anthony Curtis, a casino gambling expert who publishes the Las Vegas Advisor, told Casino.org.

It has been known for over a century that imperceptible imperfections in roulette wheels cause some numbers to come up more frequently than randomness would dictate. These imperfections may come from the manufacturing process, wear and tear on the wheel’s drum, a damaged wheel shaft, or loose frets in the pocket dividers.

The first mention Curtis could cite was in Allan Wilson’s “Casino Gambler’s Guide.” Published in 1965, this book contains four chapters on roulette that describe a casino mechanic named Joseph Jagger, who used this method in 1873 to beat the roulette tables of Monte Carlo.

“Wilson explains the process well,” Curtis said, “emphasizing the need to accurately ‘clock’ many wheels, meaning to watch and record thousands of spins before information identifying bias becomes reliable.”

Additional information on this technique, and fascinating stories of other wheel-beaters, can also be found in the 1992 book, “Beating the Wheel,” by Russell T. Barnhart.

Did Garcia-Pelayo Get Away With It?

Yes, though not without a nail-biting hassle. In 1994, Casino Gran Madrid sued him for an unspecified amount of its money back. The casino lost and its ban was overturned by a judge who ruled that no cheating occurred. But the casino appealed.

It wasn’t until 10 years later that Spain’s Supreme Court upheld the lower court’s ruling, writing that Garcia-Pelayo used “ingenuity and computer techniques, that’s all.”

Can the System Still Work Today?

Technically, yes, but only if you can locate a biased wheel. And good luck with that.

Since this scandal broke, all major casinos have implemented automatic bias corrections to their roulette wheels. Ironically, they employ the same method to do so that Garcia used — computer analysis of spin randomness.

As soon as any wheel shows any bias, the house quickly changes it out.

In addition, technological advancements made in the interim reduce roulette wheel manufacturing biases, and casinos now commonly employ Starburst roulette wheels. These incorporate metal frets, which wear at a slower rate than their old wooden counterparts.

Look for “Vegas Myths Busted” every Monday on Casino.org. Click here to read previously busted Vegas myths. Got a suggestion for a Vegas myth that needs busting? Email corey@casino.org.