Premise: Arturo Guzmán Decena (a.k.a. Z-1) (13 January 1976 – 21 November 2002) was a Mexican Army Special Forces operative who in 1997 defected to the Gulf Cartel and subsequently founded the criminal syndicate's enforcement wing at the behest of drug baron Osiel Cárdenas Guillén. Known today as Los Zetas, the cartel's armed wing ultimately broke apart and formed its own drug trafficking organization.
Hypothesis: Arturo Guzmán Decena was asked to defect by Osiel Cárdenas.