For 150 years, judges and legal scholars said that the Texas pleading system came from Spain. They explained that Mexico used a simple Spanish pleading system that English-speaking immigrants to Mexican Texas liked more than the complicated procedure they had known in the United States. After separating from Mexico, the story goes, Texas retained the Spanish system.
But that story is probably wrong. The Republic of Texas enacted its first pleading law in 1836. It does not look like Spanish pleading laws; it looks like an 1824 law written by Stephen F. Austin for his colony’s alcalde courts. Austin’s law looks like an 1805 Louisiana law written by Edward Livingston. The Austin and Livingston laws use the words of English equity.
The story does not end there, however. Equity and Spanish pleading are related. And Livingston was influenced by Jeremy Bentham, who admired the simplified judicial procedures of the Arab al-qadi, an ancient judicial office that became the alcalde of Spain, Mexico, and Texas. Above all, Austin and Livingston liked Spanish law and tried to conform their laws to its principles out of sincere respect for Hispanic culture and institutions. So, Texas pleading law is partly Spanish, even if it came from England.
Joseph McKnight published more research on the origin of Texas law than anyone else. His scholarship was the key to understanding the true origin of Texas pleading.
Justice Jason Boatright, The Curious Origin of Texas Pleading, 71 SMU L. Rev. 39 (2018)