CHICAGO (CBS) — A Chicago federal judge has quashed a bid by a star witness against Mexico’s most notorious drug lord to shave time off his prison sentence.

Court filings unsealed Monday reveal that Chicago-born drug trafficker Pedro Flores asked in July for a reduction of his 14-year prison term for risking his life in testifying against Joaquin “El Chapo” Guzman last year. Flores said he went beyond his cooperation agreement with prosecutors in testifying against Guzman in New York.

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Monday’s filings include transcripts of an August hearing at which Judge Ruben Castillo rejected Flores’ request.

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Twin brothers Pedro and Margarito Flores were sentenced to 14 years each for drug conspiracy charges. They became informants against the Sinaloa Cartel, in exchange for reduced charges, and helped the feds nab cartel boss Joaquin “El Chapo” Guzman (Undated wanted poster photos)

Castillo said he already factored in the extensive help Flores and his twin brother, Margarito, provided U.S. agents when handing them sharply reduced 14-year prison terms for trafficking in 2015. Absent their cooperation, they would have been sentenced to life behind bars.

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