According to a law approved by the Texas Congress on December 21, 1836, "Every person who shall kill another in a duel, shall be deemed guilty of murder, and on conviction thereof shall suffer death," and "Every person who shall be the bearer of any challenge for a duel, or shall in any way assist in any duel, shall, on conviction thereof, be fined and imprisoned at the discretion of the court before whom such conviction may be had."

http://www.tshaonline.org/handbook/online/articles/DD/jgd1.html