The Guerrero Decree, which abolished slavery throughout the Republic of Mexico except in the Isthmus of Tehuantepec, was issued by President Vicente R. Guerrero on September 15, 1829. Guerrero may have acted under the influence of José María Tornel, who hoped the decree would be a check on American immigration, or he may have issued it as a personal measure because his enemies accused him of being partly of African descent. The decree reached Texas on October 16, but Ramón Músquiz, the political chief, withheld its publication because it was in violation of the colonization laws, which guaranteed the settlers security for their persons and property. The news of the decree did alarm the Texans, who petitioned Guerrero to exempt Texas from the operation of the law. On December 2 Agustín Viesca, secretary of relations, wrote the governor of Texas that no change would be made respecting the slaves in Texas. Though the decree was never put into operation, it left a conviction in the minds of many Texas colonists that their interests were not safe.