A strong RICO defense often starts by challenging the alleged enterprise. The government must prove that an organized enterprise existed and that the defendant participated in its affairs. A loose group of people involved in separate conduct does not automatically qualify as a RICO enterprise.

The defense can also challenge the pattern of racketeering activity. Prosecutors need at least two related predicate acts that show continuity. Isolated events, unrelated accusations, or conduct over a short period may fail to establish the pattern required for a RICO conviction.

Other defenses include attacking the evidence behind each predicate offense, challenging witness credibility, showing the defendant lacked knowledge of the enterprise, and proving that the conduct involved legitimate business activity rather than criminal conduct.