1. The Federal Government regulates how information may be used to buy and sell securities. The SEC has rules around insider trading, so that if you have inside knowledge you can't profit off of it.
2. Deposit Insurance: The FDIC requires a certain amount of cash reserves to ensure that checking accounts will always be protected
3. Commodity Future Trading Commission regulates the commodity market in ways to ensure that the commodities markets are not manipulated and investigates and prosecutes people abusing the system.