Regarding elements of a RICO offense, the law prohibits "any person" from using income derived from a pattern of racketeering activity or from the collection of an unlawful debt to acquire an interest in an enterprise affecting interstate commerce; acquiring or maintaining, through a pattern of racketeering activity or through collection of an unlawful debt, an interest in an enterprise affecting interstate commerce; conducting or participating in the conduct of the affairs of an enterprise affecting interstate commerce through a pattern of racketeering activity or through collection of an unlawful debt; or conspiring to participate in any of the aforementioned activities. In order to convict a defendant under RICO, the prosecution must prove that the defendant, through the commission of two or more acts constituting a pattern of racketeering activity, directly or indirectly invested in, maintained an interest in, or participated in an enterprise whose activities affected interstate or foreign commerce. Potential defenses to RICO charges pertain to the invalidity of one or more predicate acts that support a RICO offense; statute of limitations; the defendant's withdrawal from a conspiracy; and challenges based on "primary jurisdiction," "horizontal preemption," and "reverse vertical preemption." Constitutional challenges to RICO are also discussed. The article's section on criminal penalties addresses asset forfeiture and sentencing. The section on RICO civil proceedings focuses on civil penalties and a civil cause of action for private parties. The discussion of recent developments regarding RICO considers protests, tobacco litigation, heath-care fraud, and police misconduct. 354 notes