Racketeering and RICO charges are complex and usually involve a lot of evidence collected over a long time frame by many law enforcement agencies.
This means that the police and government had many chances to make mistakes in gathering evidence against you. Illegally seized evidence can be thrown out of the case by an experienced criminal defense lawyer.
Another defense to racketeering is evidence showing that the underlying crimes were not interrelated or committed to advance a single purpose. This is the heart of a racketeering case, and if it can be disproven, you should be acquitted of the charges.