My name is Stephen Dudley, and I'm the co-director of InSight Crime.

Over the years, I've done numerous reports about presidential candidates and presidents themselves doing nefarious things. These are some of the most difficult reports you can do, because you really have to have things nailed down tight, solid sourcing numerous sources, corroboration. You know what they say; you aim at the King, you better not miss.

One of those stories was about Álvaro Colom, the now deceased former president of Guatemala, and his 2007 bid to become president. The story was about how the Zetas, the vicious Mexico based criminal group, had given his campaign an over $11 million contribution.

Well, not that we needed it, but we recently got more corroboration of this story. It came from one of the city's leaders at the time, a guy named Jose María Guizar Valencia alias Z-43. Guizar Valencia, recently told the US court during a trial that he and his cohorts had given Colom not $11 million but $24 million in campaign contributions.

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