Rule #1 - Never let suspects stay together.
Tony's idea to bring the hackers to NCIS was implemented, and that meant they would all share a transport from prison. This violated Rule #1 in a major way. It gave the inmates time to formulate a strategy for handling NCIS and foiling their investigation. It didn't work because NCIS is awesome, but what does that say about the consequences of breaking Gibbs' Rules?
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