Blackjack is one of the most popular games in Black Hawk and Central City, and card counting is one of the most misunderstood topics in gambling. Some people think it's a crime. Others think casinos can't do anything about it. The truth is somewhere in between.
Counting cards in your head is not a crime
In Colorado, as in the rest of the United States, there is no law against keeping track of the cards using your own memory and judgment. Card counting is a mental strategy. You're using information that's in plain view on the table to adjust your bets and decisions. Being good at math is not a crime.
But casinos don't have to let you play
Colorado casinos are private businesses, and they have wide latitude to decide whom they'll serve. If a casino believes you're counting cards, it can legally:
- Limit your bets or only allow you to bet the same amount every hand ("flat betting")
- Shuffle more often, or move you to a game with a continuous shuffling machine
- Ask you to stop playing blackjack
- Ask you to leave the property and ban you from coming back
Being asked to leave isn't an arrest, and it doesn't create a criminal record. But what you do next matters. If you've been told to leave or formally banned, refusing to go, or coming back later, can lead to a trespass charge. A legal strategy can turn into an actual criminal case simply by ignoring a ban.
Where it becomes a crime: devices and cheating
Colorado's Limited Gaming Act (C.R.S. Title 44, Article 30) draws a sharp line between what you do with your mind and what you do with outside help. Using or possessing a device to count cards, calculate odds, or predict outcomes is a crime. That includes phone apps, hidden computers, and electronic signaling equipment.
Other conduct that's treated as cheating includes:
- Marking cards or tampering with the deck or equipment
- Past posting, which means adding to or changing a bet after the outcome is known
- Colluding with a dealer or other casino employee
- Manipulating machines or the outcome of any game
These are investigated by the Colorado Division of Gaming, often together with Black Hawk police in Black Hawk or the Gilpin County Sheriff's Office in Central City. They are prosecuted by the First Judicial District Attorney, and some are felonies.
Gray areas and "advantage play"
Card counting is just one form of what gamblers call "advantage play." Some other techniques, like spotting a dealer who accidentally exposes cards, sit in grayer territory. Whether conduct like that is legal can depend on exactly what happened and whether the player did anything to cause it. If a casino or the Division of Gaming accuses you of cheating based on an advantage-play technique, the details matter. Don't try to explain them to security on your own.
If you're pulled off the floor
Being backed off from a table is usually just a conversation. But if security asks you to come to a back room, or a gaming investigator wants to talk, the situation has changed. Stay calm, be polite, and don't explain your strategy or answer questions about what you were doing until you've spoken with a lawyer. For more on what to expect in that room, see what happens if casino security detains you in Colorado.
Accused of cheating in a Colorado casino?
Gaming cases depend heavily on surveillance video, and the full footage often tells a different story than the clip in the report. As a former prosecutor, I know how these cases are put together and where they tend to fall apart. Learn more about defending casino and gaming charges in Central City and Black Hawk, or call for a free, confidential consultation.
This article is general information about Colorado law, not legal advice about your situation. Every case turns on its own facts, and laws change. Reading this article or contacting this office does not create an attorney-client relationship.